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52 Cards in this Set
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Symptoms
Fever, chills, hypotension, hypothermia, shock. Rash (ecthyma gan- grenosum, with Pseudomonas and others). |
Bacteremia and Septicemia
Description/Diagnosis Spread of infection to the bloodstream (bacteremia); septicemia in- cludes symptoms and infections by fungi and microbes other than bacteria. Diagnosis based on clinical scenarios. Pathology Complex. Endotoxin or other microbial elements may cause symptoms/shock. |
Treatment Steps
Antibiotics, supportive (fluids, pressors). |
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Symptoms
Fever, rash, hypotension, dermal peeling of palms and soles (skin desquamation). |
Toxic Shock Syndrome
Description Toxin-producing staphylococcal (or occasionally streptococcal) in- fection. |
Diagnosis
History and physical, tampon use, culture (vagina/blood). Treatment Steps Antibiotics (β-lactamase resistant, antistaphylococcal), remove tampon, supportive care for shock. |
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Description/Symptoms
Purulent conjunctivitis before 1 week old. |
Ophthalmia Neonatorum
Pathology Etiology in Neisseria gonorrhoeae, Chlamydia, Haemophilus. |
Treatment Steps
Antibiotics. Prevent by 1% silver nitrate or erythromycin topically |
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Description/Symptoms
Conjunctival inflammation, causing exudate, itching, eyelid edema. |
Bacterial Conjunctivitis
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Diagnosis
Clinical diagnosis, conjunctival scraping and culture used rarely. Treatment Steps Antibiotics. Topical and/or systemic |
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Description/Symptoms
Corneal infection/inflammation, causing red, painful eye, especially in children. Clinical diagnosis. |
Viral Keratoconjunctivitis
Pathology Herpes simplex most common in children, also other viruses including adenovirus (common with adult infections). |
Treatment Steps
Trifluridine or acyclovir |
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Symptoms/Diagnosis
Pain, drainage, itching. Clinical diagnosis. |
External Otitis
Description External auditory canal inflammation; swimmer’s ear Pathology • Staphylococcus epidermidis, other bacteria, fungal. If chronic, suspect Pseudomonas. • Malignant otitis (severe infection with temporal bone invasion), suspect Pseudomonas (or occasionally Proteus). |
Treatment Steps
Topical and (if necessary) systemic antibiotics. Systemic needed for malignant otitis. |
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Description/Symptoms
Middle ear inflammation, causing fever, hearing loss, pain |
Otitis Media
Pathology Streptococcus pneumoniae common. Multiple other agents possible. Common in children with eustachian tube dysfunction as possible etiology |
Diagnosis
History and physical shows loss of light reflex, possible fluid behind tympanic membrane. Treatment Steps Antibiotics (amoxicillin). If failure, use second-line antibiotic (e.g., oral cephalosporin or clarithromycin). If fails frequently, consider ear, nose, and throat (ENT) evaluation for tubes |
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Description/Symptoms
Mastoid air cell inflammation, causing fever, pain, hearing loss, postauricular swelling/erythema, displaced pinna. Cause is usually bacterial infection that started as otitis media. |
Mastoiditis
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Diagnosis
History and physical, x-ray studies (computed tomography [CT]). Treatment Steps 1. Antibiotics. 2. Myringotomy. 3. Mastoidectomy. |
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Symptoms of Bacterial Meningitis
Fever/nuchal rigidity/headache/vomiting. Brudzinski’s sign: Cervical motion elicits pain. Kernig’s sign: Painful hamstring stretch. |
Meningitis
See also Chapter 11, section VII.A. Description Brain/spinal cord membrane inflammation. Much more serious and fatal if caused by bacteria rather than virus. Pathology Spread of germs to the central nervous system (CNS) via the blood. Common germs: up to 1 month of age, Escherichia coli, and group B strep; 1 month to age 6, H. influenzae type b, S. pneumoniae, and N. meningitidis; older than 6, S. pneumoniae and N. meningitidis |
Diagnosis
History and physical. Examination of cerebrospinal fluid (CSF) (bacteria: low glucose, elevated protein, high white blood count [WBC] with predominant neutrophils, positive Gram stain; viral: normal glucose, slightly elevated protein, low WBC [< 100] with pre- dominant lymphs). Prevention of Bacterial Meningitis Immunization (Haemophilus influenzae, S. pneumoniae, and Neisseria meningitidis) and treatment/prophylaxis of exposed close contacts. Treatment Steps Antibiotics given parenterally (at high doses). (See Chapter 11, sec- tion VII.A.) |
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Symptoms
Headache, mental changes, nausea/vomiting, focal neurologic find- ings, seizures. |
Brain Abscess
Pathology Anaerobic bacteria and oral Streptococcus common. May extend from ear/sinuses, follow injury, or be bloodborne from other areas (lung). |
Diagnosis
History and physical examination, CT scan. Treatment Steps 1. Antibiotics IV. 2. Surgical drainage. |
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Symptoms
Local severe back pain changing to radicular pain, then weakness. Fever and local tenderness also. |
Spinal Epidural Abscess
Description Infrequent disease. Early intervention needed to prevent paraplegia. Pathology Bloodborne spread from skin and IV catheters, usually by Staphylococcus aureus. |
Diagnosis
History and physical examination, x-rays, CT, lumbar puncture Treatment Steps 1. Surgical drainage. 2. Antibiotics. |
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Symptoms
Fever, headache, weakness, sore throat. Muscle wasting, lower motor neuron lesion, vomiting |
Poliomyelitis
Description Poliomyelitis virus can be transmitted by fecal–oral route. Three classes of polio exist: 1. Abortive polio––a febrile illness without CNS involvement. 2. Nonparalytic polio––aseptic meningitis with complete recovery. 3. Paralytic polio––aseptic meningitis followed by development of motor weakness. |
Diagnosis
History and physical examination. Examination of CSF. Stool/ throat/fecal culture. Serologic testing to confirm (polio virus is a type of enterovirus). Treatment Steps Supportive treatment. Polio is rare due to vaccination. |
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Symptoms
Clinically, a prodrome of fever, myalgias, followed by encephalitis with confusion and agitation. Hydrophobia (laryngeal spasm with drinking or just sight of water), paresthesia/pain at bite site. Hyper- activity, ascending paralysis. Excessive salivation can cause classic “foaming at the mouth.” |
Rabies
Description Viral encephalitis caused by rabies virus. Very rare in the United States. Only several cases on record of human survival in documented rabies. |
Diagnosis
History and physical, animal bite. Check animal’s brain for rabies. Also via state lab: search for rabies virus/antigen by neck skin/cornea biopsy, and serologic screening (for antirabies antibody). Prevention Immunize high-risk individuals (veterinarians, cave explorers, animal handlers). Treatment Steps For exposure: Local wound cleaning and postexposure prophylaxis with human rabies immune globulin (HRIG), rabies vaccine. For confirmed rabies: Supportive |
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Symptoms
Tonic muscle spasms (jaw, trismus/lockjaw), rictus sardonicus: tris- mus-induced facial sneer. Opisthotonos, tetanospasm. |
Tetanus
Description Neurotoxin-induced muscle spasm disorder Pathology Clostridium tetani produces neurotoxin. Several days’ to 3 weeks’ incubation, after germ entry via wound. |
Diagnosis
History and physical examination. Treatment Steps Supportive, tetanus immune globulin, and penicillin G. |
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Symptoms
Severe headache, fever, photophobia |
Viral Encephalitis
Description CNS inflammation/infection caused by a virus (see Cram Facts) |
Diagnosis
Lumbar puncture with cell count < 100, protein < 100. Treatment Steps Supportive. |
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Symptoms
Severe headache, fever, photophobia • CT scan of head may show hypodense areas in temporal lobe(s). |
HERPES ENCEPHALITIS
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CSF can be tested for
herpes simplex using polymerase chain reaction (PCR). • Acyclovir is often started empirically while results are pending. |
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Symptoms
Usually asymptomatic; fever, headache, myalgia, adenopathy. Congenital infection (microcephaly, seizures, retinochoroiditis) |
Toxoplasmosis
Description Infection with Toxoplasma gondii usually by cyst ingestion (cat litter/ soil/undercooked meat, pregnant women must avoid all three). Also, transplacental transmission is possible. |
Diagnosis
Biopsy is definitive for cysts/trophozoites. Serologic testing. Found in people with impaired cell-mediated immunity or children of mothers who acquired toxoplasmosis during pregnancy. Treatment Steps Pyrimethamine plus sulfadiazine. |
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Symptoms
Purulent nasal discharge, tonsillar membrane, fever, cervical adenopathy, nausea/vomiting. |
Diphtheria
Description Upper respiratory tract infection caused by Corynebacterium diphtheriae. Prevent via immunization |
Diagnosis
Clinical, sore throat with green/gray pharyngeal membrane. Treatment Steps 1. Diphtheria antitoxin (DAT) and penicillin or erythromycin. 2. Penicillin or erythromycin for carrier state. |
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Symptoms
Fever, murmur, anemia. Multiple other symptoms possible including splinter hemorrhages, Osler nodes (red fingertip bumps), Janeway lesions (red macules on palms/soles), Roth spots on fundoscopic exam, weight loss, petechiae. |
Endocarditis
Description Endocardial infection. Pathology Acute often S. aureus (drug use typical). Subacute, often α-hemolytic Streptococcus viridans (oral pathology or surgery). Mitral valve most common site, pulmonic least common (in drug users, tricuspid valve more common). Platelets/fibrin form on abnormal area, then bacte- ria attach |
Diagnosis
History and physical, blood culture, echocardiogram. Treatment Steps 1. Consult current literature. 2. Streptococcus—penicillin G and gentamicin (or streptomycin). 3. Staphylococcus—nafcillin (watch for methicillin-resistant S. aureus [MRSA] for which vancomycin is indicated). Also, note association of Streptococcus bovis or Clostridium septicum and colon cancer. |
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Symptoms
After 2-week incubation, fever, headache, enlarging parotid (bilat- eral in 75%) |
Mumps
Description Contagious mumps virus (a paramyxovirus) infection, only in hu- mans. Prevented with vaccination. Most commonly causes parotidi- tis, but complications can include pancreatitis, orchitis, meningitis, encephalitis, nephritis, or deafness. |
Diagnosis
History and physical, serologic testing/viral isolation. Treatment Steps No treatment is needed. Prednisone has been used in cases of orchitis. |
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Description/Symptoms
Common oral infection, usually with herpes simplex type I. Infection may be asymptomatic, or fever, vesicles and ulcers, adenopathy |
Herpetic Gingivostomatitis
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Diagnosis/Treatment
Clinical diagnosis. Can culture if unsure of herpes vs. bacterial in- volvement. Often resolves spontaneously. Can use toical pencyclovir or systemic acyclovir. |
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Description/Symptoms
Overgrowth of Candida species, which is normally found in the body. Can cause vaginitis (vaginal itch/white thick discharge); diaper ery- thema and satellite lesions; balanitis; or oral thrush with mucosal disease and esophageal symptoms common. |
Candidiasis
Pathology Superficial fungal infection, severe mucosal infection (rule out hu- man immunodeficiency virus [HIV]) or fungemia/disseminated disease (rule out neutropenia or intravenous [IV] catheter related). |
Diagnosis
Clinical picture, potassium hydroxide (KOH) preparation Treatment Steps 1. Antifungal. 2. Topical and/or oral medication for mild disease. 3. Oral or IV fluconazole or IV amphotericin for moderate to severe disease |
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Description/Symptoms
Oral fungal infection, usually caused by Candida albicans. Removable white mouth patches, plaque, halitosis. Can progress to esophagitis and cause dysphagia. |
Thrush
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Diagnosis
History and physical exam, KOH preparation. Treatment Steps Nystatin mouth rinse and/or oral antifungal (fluconazole) |
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Symptoms/Diagnosis
Fever, neck extension. Diagnose clinically. May culture abscess |
Retropharyngeal Abscess
Description Retropharyngeal infection caused by spread of infection from local area (sinus, tooth, etc.). |
Treatment Steps
Incision and drainage, antibiotics. Monitor for airway compromise. |
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Symptoms
Nausea, vomiting, diarrhea, after food ingestion. |
Food Poisoning
Description Illness from ingestion of contaminated food. Can be due to many bacteria, viruses, or toxins |
Diagnosis
Food/stool culture and toxicologic studies. History and physical exam. Treatment Steps Symptomatic, may treat specific bacterial isolate (Clostridium difficile metronidazole or vancomycin by mouth) |
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Symptoms
Nausea, vomiting, dysphagia, diplopia, progressive paralysis hours to days after ingesting bad fish/meat or canned product. Both myas- thenia gravis and Guillain–Barré are usually considered in the differential, as they can all have ascending paralysis. |
Botulism
Description Foodborne botulism is caused by ingestion of food containing pre- formed toxin, most commonly via home-canned food. Infant botu- lism arises from ingesting spores of Clostridium botulinum, which pro- duces toxin in the GI tract. Wound botulism develops in wounds contaminated by C. botulinum (can be wounds contaminated by soil, such as in chronic IV drug users) Pathology C. botulinum produces neurotoxin. In infants, the clostridial spores can germinate in the intestine and produce toxin there |
Diagnosis
History and physical, toxin in serum/stool/food. Differs from myas- thenia gravis by negative edrophonium (Tensilon) test. Must have strong clinical suspicion, usually from a thorough history. Treatment Steps 1. Trivalent antitoxin (A, B, E) should be given as soon as possible. 2. Supportive treatment including close monitoring of airway, as respiratory failure can develop. 3. Wound botulism––exploration and debridement also needed. |
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Vomiting, diarrhea, fever,
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Viral Gastroenteritis
often due to rotavirus or Norwalk virus. |
Supportive care
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Symptoms
Malaise, delirium, headache, constipation or diarrhea, lethargy, and fever, which could last 4–8 weeks. Exam findings incllude relative bradycardia, hepatosplenomegaly, and rose spots. |
Typhoid
Description Enteric fever, caused by Salmonella typhi (a pathogen in humans only). Organism is ingested via contaminated food, water, or milk and is more common in travelers or patients with HIV. |
Diagnosis
Clinical picture, positive diagnosis by blood culture, presumptive by stool/urine culture, agglutinin titer. Treatment Steps Chloramphenicol, ciprofloxacin, amoxicillin. Dexamethasone may be used for severe typhoid |
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Symptoms
Nausea, fever, cramps, bloody diarrhea (gastroenteritis, S. enteritidis), bacteremia, or asymptomatic carrier. |
Salmonella
Description Salmonella species are found in contaminated food or drink, com- monly eggs or poultry. Can cause mild gastroenteritis or, more seri- ously, typhoid fever (see above). Immunosuppressed patients are at highest risk. |
Diagnosis
History and physical, stool culture, negative blood culture with en- teritis, may be positive with enteric fever. Treatment Steps No treatment needed for mild disease. |
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Symptoms
Range from mild watery diarrhea to more severe abdominal pain, tenesmus, bloody stool, cramping, fever. |
Shigella
Description Bacillary dysentery, caused by Shigella species. Fecal–oral and person- to-person transmission exist. At high risk are children and homosexual men, and low socioeconomic status. |
Diagnosis
History and physical, stool for WBC and culture. Treatment Steps Resistance to ampicillin now becoming more common. Other antibi- otics include ciprofloxacin, trimethoprim sulfamethoxazole, or ceftriaxone |
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Symptoms
Watery diarrhea, abdominal pain. Enteroinvasive strains present like Shigella |
Toxicogenic E. coli (including O157) Infection
Description Diarrheal illness (with blood for O157). Pathology E. coli producing exotoxin resulting in colon mucosa fluid secretion. |
Diagnosis
Culture, serologic testing Treatment Steps Hydration; try tetracycline or quinolone (no treatment known to be effective for O157). Antibiotics may increase the risk of developing hemolytic–uremic syndrome (HUS) Sequelae HUS in children with O157. |
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Symptoms
Gas gangrene: pain at wound infection, bullae, tissue gas, hypotension |
Clostridial Infection
Description Toxin-producing germs Pathology Clostridium tetani, see Tetanus section; C. perfringens, see Gas gan- grene; C. botulinum, see Botulism section; C. difficile, see Pseudomembranous colitis. |
Diagnosis
History and physical exam, Gram stain, culture Treatment Steps Gas gangrene: debridement, penicillin G |
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Symptoms
Profuse watery diarrhea (rice-water stools), with vomiting, causing dehydration. |
Cholera
Description Infectious diarrhea caused by a curved gram-negative rod, Vibrio cholerae. More common in Asia, Africa. Has occurred sporadically in the United States (Texas, Louisiana). |
Diagnosis
Culture of stool on special medium. Treatment Steps 1. Fluid replacement (lactated Ringer’s or other crystalloid). 2. In adults, single-dose tetracyline or ciprofloxacin. 3. Children––erythromycin |
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Symptoms
Watery diarrhea, tenesmus, cramps. Diarrhea may have a “characteristic” smell |
Pseudomembranous Enterocolitis
Description Antibiotic-induced colitis, caused by C. difficile, which produces a toxin causing diarrhea and a pseudomembrane in the colon |
Diagnosis
Clinical scenario, stool for C. difficile toxin. Treatment Steps Stop antibiotic; give oral metronidazole, or vancomycin if metronidazole fails. |
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Symptoms
Although asymptomatic passage of cysts can occur, symptomatic amebic colitis develops from 2 to 6 weeks after ingestion. Mild diar- rhea, lower abdominal pain, weight loss. Cecal involvement mimics appendicitis. Full-blown dysentery may occur. Stool is almost always heme positive. With fever and right upper quadrant pain, suspect liver abscess. |
Amebiasis
Description Infection with Entamoeba histolytica, an intestinal protozoan. Highest- risk groups are travelers, recent immigrants, homosexual men, poor socioeconomic status, and residents of institutions. Infection acquired by ingestion of cysts from fecally contaminated water, food, or hands |
Diagnosis
Demonstration of trophozoites or cyst of E. histolytica on wet mount, iodine stain of stool, or trichrome stains of stool. Repeated stool exams are needed. Also, differentiate from other types of Entamoeba that do not cause disease. Serology may be used. Prevention Water purification, treatment of asymptomatic carrier Treatment Steps 1. Carriers—use one of the following three luminal agents: iodoquinol, diloxanide, and paromomycin. 2. Colitis or liver abscess––a luminal agent plus and metronidazole Before starting metronidazole, warn patients about severe reaction if taken with alcohol (Antabuse-like reaction). |
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Symptoms
Range from asymptomatic to more fulminant diarrhea and malab- sorption. Incubation period 1–3 weeks. Early diarrhea, bloating, and abdominal pain. Also increased flatus and weight loss if infection is chronic. Fever, blood, or mucus in stool is rare. |
Giardiasis
Description A common parasitic infection caused by digestion of the cyst form of Giardia lamblia. Person-to-person transmission can occur, and there- fore risks include residents of institutions, children in day care centers, and homosexual men as well as poor socioeconomic status. |
Prevention
Hygiene, avoiding water while traveling, treatment of carriers. Diagnosis/Treatment Steps Finding cysts or trophozoites in the feces or small intestine. Repeat exams may be needed. Can also test for parasitic antigen in the stool. Treatment: Metronidazole |
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Symptoms
Cough, anemia, pruritus, weight loss. |
Hookworm
Description Intestinal nematode infection. Hookworm is rare in the United States, while pinworm is common. Pathology • Hookworm: Ancylostoma duodenale or Necator americanus. Cycle: eggs in feces reach soil; larvae form; larvae enter skin/blood/then lungs; larvae swallowed reach intestine. |
Treatment Steps
mild infection, none; severe, mebendazole (Vermox), or pyrantel pamoate. |
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Symptoms
Pruritus ani at night |
Pinworm
Description Intestinal nematode infection. Hookworm is rare in the United States, while pinworm is common. Pathology • Pinworm: Enterobius vermicularis. Most frequent worm infection in the United States. |
Treatment Steps
mild infection, none; severe, mebendazole (Vermox), or pyrantel pamoate. |
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Symptoms
Left lower quadrant (LLQ) pain and/or mass, constipation, chills/fever. |
Diverticulitis
Description Diverticular inflammation and perforation. |
Treatment Steps
If mild, medical (nothing by mouth [NPO], antibiotics), otherwise surgical resection. |
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Symptoms
Hepatic abscess: fever, right upper quadrant (RUQ) pain, jaundice. Intra-abdominal abscess: fever, elevated diaphragm, leukocytosis, pain |
Intra-abdominal Abscess, Hepatic/ Subphrenic
Description Hepatic abscess: local collection of pus in liver. Intra-abdominal abscess includes subphrenic abscess. Pathology E. coli common. Amebic liver abscess in high-risk individual (due to Entamoeba histolytica). |
Diagnosis
History and physical, ultrasound, CT, gallium scan, positive Hoover’s sign (x-ray sternochondral widening). Treatment Steps Surgery and antibiotics. |
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Symptoms
Can cause cutaneous symptoms (usually pruritus and a mild rash) at the area where the organism penetrated the skin, usually the feet. Pulmonary involvement can cause cough, fever, dyspnea. GI disease can cause nausea, vomiting, and diarrhea. |
Strongyloidiasis
Description A relatively uncommon condition in the United States, caused by in- fection with Strongyloides stercoralis. Endemic areas––tropics. Can be serious infection in an immunocompromised patient |
Diagnosis
Finding worm in feces or other body specimens; serology. Treatment Steps Thiabendazole; ivermectin. Prevention: wearing shoes |
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Nonspecific symptoms such as back, flank, or abdominal pain and fever.
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• Renal and perinephric abscess––often sequela from a urinary tract infection or nephrolithiasis.
Organisms include S. aureus and E. coli. |
Abscess usually seen on ultrasound or CT scan. Systemic antibiotics and drainage needed
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Pelvic abscess
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–in females often related to reproductive tract, in-
cluding septic abortion, endometritis, postoperative infection af- ter hysterectomy, or with pelvic inflammatory disease (tubo-ovarian abscess). A multitude of organisms can cause the abscess. |
Antibiotics with potent anaerobic coverage should be used w/ possible surgical exploration/drainage
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Description/Symptoms
Bacterial infection spread into lymph nodes. Exam reveals red streak extending from wound; fever, adenopathy. |
Lymphangitis
Diagnosis/Pathology Clinical diagnosis. Common cause hemolytic strep; rule out cat scratch fever. |
Treatment Steps
Antibiotics. |
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Symptoms
• Stage I––early infection. Classic erythema chronicum migrans rash: a flat to slightly raised erythematous rash with central clear- ing. Usually occurs at area of tick bite, but many persons do not recall the bite or the tick. • Stage II––disseminated infection. Secondary skin lesions can appear. Complaints include headache, stiff neck, fever, myalgias, arthralgias, and fatigue. Neurologic complaints can include cranial neuritis (par- ticularly cranial nerve VII), myelitis, or subtle encephalitis. CSF may show lymphocytes, elevated protein, and normal to low protein. Car- diac abnormalities can include arteriovenus (AV) block. • Stage III––persistent infection. Intermittent oligoarticular arthri- tis in large joints, particularly knees. |
Lyme Disease
Description Multisystem disorder caused by the spirochete Borrelia burgdorferi. Usually transmitted by the deer tick Ixodes dammini. Three stages of the disease exist |
Diagnosis
Clinical setting, but it can be difficult to diagnose. If the rash is noted in a patient who lives in or has visited an area with a high inci- dence of Lyme disease (particularly the Northeast United States), empiric treatment should be started. Serologic testing not needed,as it may come back as a false negative early in the infection. Later in the disease course, serologies can confirm infection. PCR of the CSF or joint fluid can be done to look for presence of the organism. Treatment Steps Depends on the stage and the clinical manifestations. Skin lesions: • Doxycycline 100 mg bid for 14–21 days. • Amoxicillin (used in pregnant women and children) for 14–21 days. • Arthritis. • Doxycycline or amoxicillin for 30–60 days. Neurologic or cardiac involvement: • Often requires intravenous treatment (with ceftriaxone or cefotaxime). Total duration of treatment usually at least 30 days |
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Symptoms
Initially nonspecific: Malaise, headache, fatigue, myalgias, abdomi- nal pain, followed by fevers. Classic malaria paroxysms where fever spikes and chills occur at regular intervals suggests infection with P. vivax or P. ovale. |
Malaria
Description The most important parasitic infection in humans, causing up to 3 million deaths per year worldwide. Infection with one of the follow- ing four Plasmodium species: P. vivax, P. ovale, P. malariae, and P. falci- parum. Disease found in the tropics and transmitted via mosquitoes. Prevention with antimalarial drugs is of utmost importance in travel- ers, and is guided by the resistance patterns of the Plasmodium species in the particular area they are visiting. |
Diagnosis
Thick and thin smears of the blood should be done. The parasite can be visualized on these smears. Repeated smears should be exam- ined on successive days before the diagnosis is excluded. Infection with P. falciparum versus other species should be defined. Treatment Steps 1. Antimalarials include chloroquine, sulfadoxin/pyrimethamine, mefloquine, quinine, quinidine. 2. Prophylactic medications include chloroquine (where resistance is not a problem), mefloquine, doxycycline. |
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Symptoms
Variable depending on stage of disease and OIs. Primary infection with HIV is often asymptomatic; but a viral illness occurring with acute HIV infection has been described. Symptoms are nonspecific (fever, fatigue, rash, lymphadenopathy, night sweats) but if sus- pected clinically, HIV can be diagnosed if blood is sent for HIV RNA via PCR. |
HIV/AIDS (Human Immunodeficiency Virus/
Acquired Immune Deficiency Syndrome) Description (See Chapter 7, section I.B, for epidemiology, impact, and screen- ing.) Infection with the retrovirus HIV is the cause of AIDS. The pri- mary target for HIV is the CD4 T lymphocyte. HIV infection causes CD4 counts to decrease, resulting in a strong inverse relationship be- tween CD4 count and the risk of opportunistic infections (OIs). Pa- tients can be infected with HIV but not have AIDS. AIDS occurs in an HIV-positive patient whose CD4 count is < 200, has had one of many AIDS-defining illnesses (including Pneumocystis carinii pneu- monia [PCP], disseminated or Kaposi’s sarcoma, extrapulmonary histoplasmosis, cerebral toxoplasmosis, esophageal candidiasis). Diagnosis Patient consent must be obtained prior to testing for HIV. Screen- ing for HIV antibody is done first with enzyme-linked immunosor- bent assay (ELISA). If the first ELISA screen is positive, the test is re- peated. If positive a second time, confirmatory testing is done with Western blot. If HIV diagnosed, patient’s total CD4 count and viral load (using PCR for HIV RNA) should be obtained. |
Treatment Steps
1. Antiretroviral treatment. There are multiple drugs used in the treatment of HIV/AIDS, and their management should be by an infectious disease/HIV specialist. Drugs are given in combina- tion. Drug resistance patterns can be identified. Goals of therapy are to raise the CD4 count and suppress the HIV viral load (to undetectable levels, if possible). • Nucleoside analog reverse transcriptase inhibitors: • AZT (zidovudine, Retrovir). Not used with d4T. Side effects: Headaches, stomach upset, anemia, neutropenia, myopathy. • ddI (didanosine, Videx). Side effects: Pancreatitis, fat redis- tribution, peripheral neuropathy. • ddC (zalcitabine Hivid). Side effects: Pancreatitis and periph- eral neuropathy. • d4T (stavudine, Zerit). Side effects: Pancreatitis, fat redistri- bution, peripheral neuropathy. Not be used with AZT. • 3TC (lamivudine, Epivir). Side effects: Headaches and insom- nia; pancreatitis, particularly in pediatric patients. • Abacavir (Ziagen, Epzicom). A potentially serious hypersensi- tivity reaction occurs in about 3% of patients; begins days to 4 weeks after starting the drug, and resolves without further problem if the drug is stopped and not restarted. Symptoms include fever, nausea, malaise, and possibly rash. If hypersen- sitivity is suspected, Abacavir should never be restarted, since restarting can cause a more serious and possibly fatal reac- tion. • Emtricitabine (Truvada). Side effects: Gastrointestinal (GI) upset, hyperpigmentation of palms or soles. • Tenofovir (Viread). Bioavailability enhanced by a high-fat meal. Side effects: GI upset, fat redistribution, lactic acidosis. • Non-nucleoside reverse transcriptase inhibitors: • Nevirapine (Viramune). Side effects: Severe hepatotoxicity or Stevens–Johnson syndrome. • Delavirdine (Rescriptor). Side effects: Rash, GI upset, abnor- mal liver function tests. • Efavirenz (Sustiva). Side effects: CNS and psychiatric side ef- fects, fat redistribution. • Protease inhibitors: • Saquinavir (Fortovase, Invirase). Works well with ritonavir, lowering doses of both drugs. Side effects: stomach upset, ele- vated liver enzymes. INFECTIOUS AND PARASITIC DISEASES Infectious Diseases by System 242• Ritonavir (Norvir). Multiple drug interactions. Side effects: GI upset, generalized discomfort, tingling or numbness around the mouth. • Indinavir (Crixivan). Avoid dehydration, as drug can precipi- tate and cause nephrolithiasis. • Nelfinavir (Viracept). Side effects: Fat redistribution, stom- ach upset, diarrhea. • Atazanavir (Reyataz). Side effects: GI upset, hyperglycemia, fat redistribution. • Fusion inhibitor: • Enfuvirtide (Fuzeon). Subcutaneous injection. Side effects: Peripheral neuropathy, pancreatitis, elevated liver enzymes. • Combination pills: • Combivir––AZT and 3TC • Kaletra––lopinavir and ritonavir • Trizivir––abacavir, zidovudine, lamivudine 2. Prevention of opportunistic infections. Prophylaxis for certain conditions is based on CD4 count. • CD4 < 200: • P. carinii pneumonia––regimen of choice is trimethoprim– sulfamethoxazole (alternative regimens include dapsone, pentamidine). • CD4 < 100: • Toxoplasma gondii––in patients with serum anti-Toxoplasma an- tibodies, regimen of choice is trimethoprim–sulfamethoxazole (alternative regimens include dapsone/pyramethamine/ leukovorin, atovaquone). • CD4 < 50: • M. avium complex––azithromycin weekly or clarithromycin daily. • Other considerations: • M. tuberculosis––primary prophylaxis indicated for patients with a positive purified protein derivative (PPD) (induration > 5 mm) who have never been treated for tuberculosis, and patients with recent exposure to someone with active tuber- culosis, regardless of CD4 count. Depending on drug resis- tance patterns, regimens vary. • Primary prophylaxis is not routinely recommended against herpesviruses (cytomegalovirus [CMV], herpes simplex virus, and varicella–zoster virus) or fungi (Candida species, Cryptococ- cus neoformans, Histoplasma capsulatum, and Coccidioides immitis). 3. Treatment of opportunistic infections as appropriate. Examples: • Bactrim/pentamidine for PCP • Pyrimethamine for toxoplasmosis • Amphotericin for cryptococcal meningitis • Ganciclovir for CMV |
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Symptoms
Painless chancre generally appears within 2–6 weeks of infection, most commonly on the penis, vulva, or vagina,but can develop on the cervix, tongue, lips, or other parts of the body. Associated with lymphadenopathy. Chancre heals within 4–6 weeks even without treatment, but lymphadenopathy can be per- sistent. If not treated during the primary stage, about one-third of people will go on to the chronic stages. |
• Primary syphilis:
Description Infection with the spirochete Treponema pallidum, transmitted sexu- ally (or from mother to fetus). Four stages of disease––primary, sec- ondary, latent, and tertiary. An infected, untreated person is contagious during the first two stages, which usually last 1–2 years |
Treatment Steps
Diagnosis Serologic testing most often used for diagnosis. Nontreponemal tests (Venereal Disease Research Laboratory [VDRL] and rapid plasma reagin [RPR]) are used as initial screening test and become negative with treatment. Specific treponemal tests (fluorescent treponemal antibody absorption test [FTA-ABS]) are more specific and confirm syphilis when positive, and remain positive even after therapy. Dark- field examination can be used to evaluate suspicious moist cutaneous lesions. All patients with syphilis should undergo HIV testing. 1. Primary, secondary, or early latent––penicillin G (2.4 million units IM, once). |
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Symptoms
Includes rash, lymphadenopathy, and constitu- tional symptoms. A skin rash begins as pale, pink to red macules which can progress to papules or pustules. Rash can occur any- where, but almost always on the palms and soles. Papules can en- large, usually in intertriginous areas, to form moist pint-gray le- sions called condylomata lata, which are highly infectious. Rash usually heals within several weeks or months. Constitutional symp- toms can occur (mild fever, fatigue, headache, sore throat), may be very mild, |
Secondary syphilis
Description Infection with the spirochete Treponema pallidum, transmitted sexu- ally (or from mother to fetus). Four stages of disease––primary, sec- ondary, latent, and tertiary. An infected, untreated person is contagious during the first two stages, which usually last 1–2 years Constitutional symp- toms can occur (mild fever, fatigue, headache, sore throat), may be very mild, and, like primary syphilis, will disappear without treatment. The signs of secondary syphilis may come and go over the next 1–2 years of the disease. |
Treatment Steps
1. Primary, secondary, or early latent––penicillin G (2.4 million units IM, once). |
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Positive lab testing for syphilis in a patient with no
clinical manifestations of syphilis and a normal CSF exam indicate latent syphilis. |
Latent syphilis
• Early latent––latency within the first year after infection • Late latent––latency after 1 year of infection Description Infection with the spirochete Treponema pallidum, transmitted sexu- ally (or from mother to fetus). Four stages of disease––primary, sec- ondary, latent, and tertiary. An infected, untreated person is contagious during the first two stages, which usually last 1–2 years Constitutional symp- toms can occur (mild fever, fatigue, headache, sore throat), may be very mild, and, like primary syphilis, will disappear without treatment. The signs of secondary syphilis may come and go over the next 1–2 years of the disease. |
Treatment Steps
1. Primary, secondary, or early latent––penicillin G (2.4 million units IM, once). 2. Late latent (or latent of uncertain duration), cardiovascular, or benign tertiary)––penicillin G (2.4 million units IM weekly for 3 weeks) (lumbar puncture should be done in these cases, and if abnormal, treat as neurosyphilis even if asymptomatic). |
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One-third of people who have had secondary
syphilis develop tertiary syphilis (includes neurosyphilis, cardiovas- cular syphilis, and gummas). • Neurosyphilis––meningeal involvement (usually within the first year of infection), general paresis (after about 20 years), and tabes dorsalis (after 25–30 years). • Cardiovascular syphilis––includes aortitis, aortic regurgitation, saccular aneurysm. • Gummas––granulomatous inflammatory lesions; involves skin, bones, mouth, upper respiratory tract, larynx, liver, stomach |
Tertiary syphilis
Description Infection with the spirochete Treponema pallidum, transmitted sexu- ally (or from mother to fetus). Four stages of disease––primary, sec- ondary, latent, and tertiary. An infected, untreated person is contagious during the first two stages, which usually last 1–2 years. Diagnosis Serologic testing most often used for diagnosis. Nontreponemal tests (Venereal Disease Research Laboratory [VDRL] and rapid plasma reagin [RPR]) are used as initial screening test and become negative with treatment. Specific treponemal tests (fluorescent treponemal antibody absorption test [FTA-ABS]) are more specific and confirm syphilis when positive, and remain positive even after therapy. Dark-field examination can be used to evaluate suspicious moist cutaneous lesions. All patients with syphilis should undergo HIV testing. |
Treatment Steps
1. Primary, secondary, or early latent––penicillin G (2.4 million units IM, once). 2. Late latent (or latent of uncertain duration), cardiovascular, or benign tertiary)––penicillin G (2.4 million units IM weekly for 3 weeks) (lumbar puncture should be done in these cases, and if abnormal, treat as neurosyphilis even if asymptomatic). 3. Neurosyphilis––penicillin G 12–24 million units daily given intra- venously in divided doses q4h for 10–14 days |
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PUPIL Reacts to
accommodation but not to light |
ARGYLL–ROBERSTON PUPIL
• Occurs in general paresis and tabes dorsalis |
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