4 Flashcards
7–year–old with a swollen 3 x 4 cm tender, erythematous, anterior cervical neck node. Pet cat. What is the diagnosis?
Cat–scratch disease.
What is the clinical presentation of cat–scratch disease?
3–5 mm red to white papules along a linear scratch plus chronic lymphadenitis. Fever, malaise, headache, anorexia. Abdominal pain, weight loss, hepatosplenomegaly, osteolytic lesion. Parinaud oculoglandular syndrome.
What is parinaud oculoglandular syndrome?
Unilateral conjunctivitis, preauricular lymphadenopathy, cervical lymphadenopathy; caused by Bartonella; occurs after rubbing eye after touching a pet.
How is cat–scratch disease diagnosed?
History of scratch from cat. Tissue: PCR and Warthin–Starry stain (shows gram–negative bacilli). Serology: variable immunoglobulin IgG and IgM response.
What is the treatment for cat–scratch disease?
Azithromycin. Usually self–limiting and resolves in 2–4 months. Aspiration of large and painful lesions.
9–year–old child with a positive tuberculin skin test. What is the diagnosis?
Latent tuberculosis.
What are the high–risk reservoirs for Mycobacterium tuberculosis?
Recent immigrants, low socioeconomic status, HIV, elderly.
What is primary complex tuberculosis?
Tuberculosis infection of the lung with hilar adenopathy. Latent infection: reactive TB skin test and absence of clinical or radiographic findings.
How is latent tuberculosis diagnosed?
Delayed hypersensitivity skin testing: Mantoux (PPD) test. Positive 4–8 weeks after inhalation. Positive reaction is 5, 10, or 15 mm, depending on risk factors. Negative chest x–ray. No clinical disease.
How is primary tuberculosis diagnosed?
Best test is to get sputum. If unable to obtain sputum, collect 3 consecutive early AM gastric aspirates (only 50% sensitive, even with PCR). A negative culture never excludes the diagnosis.
What is the clinical presentation of primary tuberculosis?
Primary TB is asymptomatic in children. Low fever, mild cough, malaise that resolve in 1 week. Reactivation is rare and occurs during adolescence. Small number with extrapulmonary presentation; symptoms depend on location.
What is the presentation of primary pulmonary tuberculosis?
Localized nonspecific infiltrate. Large adenopathy compared to infiltrate. Compression causes atelectasis and hyperinflation. Most resolve completely.
What is the presentation of extrapulmonary tuberculosis?
Erosion into blood or lymph causes miliary tuberculosis. Lungs, spleen, liver, bone and joints: Pott disease (destruction of vertebral bodies leading to kyphosis).
What are the signs of tuberculosis meningitis?
Mostly affects brainstem. Cranial nerve III, VI, VII palsies and communicating hydrocephalus.
What is the treatment for latent tuberculosis?
INH x 9 months.
What is the treatment of primary pulmonary tuberculosis?
Isoniazid, rifampin for 6 mth. Plus pyrazinamide in first 2 mth. If increased community resistance, add streptomycin, ethambutol or ethionamide. Corticosteroids in meningitis, severe miliary disease, pericardial/pleural effusions.
What are the criteria for a positive Mantoux test reaction?
A reaction of >5 mm is positive in those who have been exposed to TB or are immunocompromised. >10 mm of induration is positive in high–risk populations. For low–risk persons, >15 mm is positive.
What are the causes of a false–negative PPD reaction?
Immunocompromise, malnourishment, or received live–virus vaccines may cause a false–negative reaction.
What is bacille Calmette–Guerin (BCG)?
BCG is not routinely used because of time–limited efficacy. Only used in high–risk with close or long–term exposures; continuous exposure to resistant strains. Contraindicated in primary or secondary immune deficiencies.
What is the treatment of perinatal tuberculosis if the mother has a positive PPD and negative chest x–ray?
No separation, no evaluation of baby. Mother and baby are given INH for 9 months. If mother has suspected TB at delivery, then separate baby from mother until chest x–ray obtained. If positive, keep separate until sputum culture results.
What is the treatment of perinatal tuberculosis if the mother has active tuberculosis?
If mother has disease, then treat infant with INH with no further separation from mother and treat mother with anti–TB therapy for 3 months. Then PPD skin–test infant: Negative, then stop INH. Positive, then continue for 9–12 months.
What is the triad of Lyme disease?
Rash. Bell palsy or carditis. Arthritis.
7–year–old child with a rash after camping in Connecticut with his family. Rash has a red raised border with central clearing. What is the diagnosis?
Lyme disease.
What is Borrelia burgdorferi?
Most common vector–borne disease in the United States. Southern New England, eastern Middle Atlantic states, and upper Midwest, with small area along the Pacific coast. The vector is Ixodes scapularis, i.e., the deer tick.
What is the clinical presentation of early Lyme disease?
History of tick bite is usually absent. History of being in woods. Erythema migrans 3–32 days after bite at the site; target lesion (>10 cm in diameter). Fever, headache, malaise. Without treatment, the lesion resolves in 1–2 weeks.
What are the signs of early disseminated Lyme disease?
Secondary lesions, which are smaller than the primary lesion, plus constitutional symptoms plus lymphadenopathy. Uveitis and Bell palsy (may be only finding); carditis (myocarditis, heart block). CNS findings (neuropathy, aseptic meningitis).
What are the signs of late Lyme disease?
Arthritis weeks to months later; affecting large joints, more likely to be chronic in adults.
How is Lyme disease diagnosed?
History plus rash. Serum antibodies for confirmation. Quantitative ELISA test and confirmatory Western blot if the ELISA is positive or equivocal.
What is the treatment of early Lyme disease?
Doxycycline 14–21 days (>8 yr); amoxicillin (
10–year–old with fever, headache, and a rose–colored rash that began on his ankles and is spreading. Camping in North Carolina. What is the diagnosis?
Rocky Mountain spotted fever
What is the geography of Rocky Mountain spotted fever?
Seen in every state; most in Southeast, especially in North Carolina. Wooded areas, coastal grasses, and salt marshes. Most April–September; most patients
What is the clinical presentation of Rocky Mountain spotted fever?
Incubation period 2–14 days, then headache, fever, anorexia, myalgias, gastrointestinal symptoms. After third day: skin rash or extremities first (palms, soles). Spreads rapidly.
What are the physical signs of Rocky Mountain spotted fever?
Rash becomes petechial and hemorrhagic. Palpable purpura. Vascular obstruction because of vasculitis and thromboses. Hepatosplenomegaly. Delirium, coma. Myocarditis, acute renal failure, pneumonitis, shock.
How is Rocky Mountain spotted fever diagnosed?
Confirm with fourfold increase in antibody titer. Normal to decreased WBC with marked left shift. Low platelet count. Hyponatremia.
What is the treatment for Rocky Mountain spotted fever?
Doxycycline or tetracycline for all patients regardless of age.
Infant with white plaques on buccal mucosa that are difficult to scrape off. When removed, there is punctate bleeding. History of antibiotics for Streptococcus infection. What is the diagnosis?
Oral candidiasis.
What is Candida albicans?
C. albicans is part of normal gastrointestinal tract and vaginal flora. Oral infection is thrush; white plaques; seen with antibiotic treatment and immunodeficiency; punctate bleeding with scraping.
What is the treatment for thrush?
Oral nystatin gargles; if recalcitrant or recurrent, single–dose fluconazole.
What is diaper dermatitis?
Confluent, papular erythema with satellite lesions of intertriginous areas of perineum.
How is diaper dermatitis diagnosed?
Skin scrapings; see yeast with KOH prep.
What is the treatment for candida diaper dermatitis?
Topical nystatin; if significant inflammation, add 1% hydrocortisone for 1–2 days.
How is catheter–related fungemia diagnosed?
Buffy coat of catheter tips, urine shows yeast; culture.
What is the treatment for catheter–related fungemia?
Remove all catheters; amphotericin B is drug of choice.
What is chronic mucocutaneous candidiasis?
Chronic mucocutaneous candidiasis is a primary defect of T lymphocytes in response to Candida; often with diabetes mellitus or autoimmune disease.
What is the triad of Rocky Mountain spotted fever?
Headache; fever; pale, rose–colored, maculopapular rash.
What is the source of Cryptococcus neoformans infection?
Soil contaminated with bird droppings, or in fruits, vegetables. Predominant fungal infection in HIV; rare in immunocompetents. Inhalation spores; disseminate to brain, meninges, skin, eyes, and skeletal system; forms granulomas.
What is the presentation of Cryptococcus neoformans infection?
Pneumonia is most common presentation; often asymptomatic, progressive pulmonary disease.
How is Cryptococcus neoformans infection diagnosed?
Latex agglutination for cryptococcal antigen in serum; most useful for CSF infections. India ink preparation for CSF is less useful than culture and antigen detection.
What is the treatment for Cryptococcus neoformans infection?
Oral fluconazole for 3–6 months if immunocompetent and only mild disease. Amphotericin B and flucytosine if immunocompromised. In HIV: lifelong prophylaxis with fluconazole.
12–year–old with flu–like symptoms for 6 days, fever, cough, and malaise. Exposure to mountain caves. What is the diagnosis?
Histoplasmosis.
What is the source of infection for Histoplasma capsulatum?
Soil contaminated with bird droppings or decayed wood; throughout Midwest, especially Ohio and Mississippi River valleys. Bat droppings in caves. Inhalation of micronidia causes proliferate as yeast.
What is the pathophysiology of Histoplasma capsulatum infection?
Bronchopneumonia (granuloma and central necrosis) that disseminates through reticuloendothelial system; resolves over 2–4 months; may calcify and appear similar to tuberculosis.
What is the clinical presentation of acute pulmonary histoplasmosis?
Most asymptomatic. Symptomatic in young children causing flu–like symptoms, hepatosplenomegaly, respiratory distress. Most have normal chest x–ray or patchy bronchopneumonia and hilar adenopathy.
What is the presentation of chronic pulmonary histoplasmosis?
Seen in adults (rarely in children) as a centrilobular emphysema.
What is the presentation of progressive disseminated histoplasmosis?
Infants, immunosuppressed. Fever, HSM, anemia, thrombocytopenia. Weight loss, interstitial pulmonary disease, oropharyngeal ulcers, meningitis. AIDS–defining: presents with fever, weight loss, lymphadenopathy, rashes.
How is histoplasmosis diagnosed?
Radioimmunoassay of serum or urine for the antigen. Blood culture is sterile; sputum may be positive or negative. Seroconversion.
What is the treatment for histoplasmosis?
None for mild acute disease or oral itraconazole. Progressive pulmonary disease or disseminated infection should be treated with amphotericin B.
16–year–old in Arizona with fever, headache, malaise, chest pain, and dry cough. Maculopapular rash and tibial erythema nodosum. What is the diagnosis?
Coccidiomycosis.
What is the presentation of coccidiomycosis?
Flu symptoms, chest pain, dry, cough, maculopapular rash, tibial erythema nodosum. Dissemination can be fatal; more common in males, Filipino/Asians, blood group B. Inhaled arthroconidia from dust; no person–to–person spread.
How is coccidiomycosis diagnosed?
Sputum obtained via bronchoalveolar lavage or gastric aspirates.
What is the triad of Coccidiomycosis?
Flu–like symptoms sometimes chest pain, maculopapular rash, erythema nodosum.
How is coccidiomycosis diagnosed?
Confirmed by culture, PCR.
What is the treatment for coccidiomycosis?
For those at high risk of severe disease, treatment with itraconazole or amphotericin B.
Unimmunized child with coryza, cough, conjunctivitis, fever. Morbilliform rash that began on head and spread caudad, including palms. Grayish white dots on buccal mucosa next to third molar. What is the diagnosis?
Measles
What is measles?
Rubeola. RNA Paramyxovirus, very contagious. Incubation–10–12 days before prodrome of cough, coryza, conjunctivitis. Koplik spots (grayish–white spots on buccal mucosa); cervical lymphadenitis. Rash and fever.
What are the characteristics of the measles rash?
Macular rash; starts at head and spreads downward.
How is measles diagnosed?
Rarely may need titers or demonstration of multi–nucleated giant cells in nasal mucosal smears for confirmation.
What are the complications of measles?
Otitis media (most common), pneumonia, encephalitis.
5–year–old unimmunized child with low–grade fever, pinpoint rash, post–occipital and retroauricular lymphadenopathy, and rose spots on the soft palate. What is the diagnosis?
Rubella
What is Rubella?
German measles. Incubation 14–21 days; contagious 2 days before rash and 5–7 days after rash.
What is the triad of rubella?
Maculopapular rash. Posterior cervical lymphadenopathy. Polyarthritis.
What is the clinical presentation of rubella?
Rash similar to measles, begins on face and spreads to body, lasts 3 days. Rash, fever concurrent. Retroauricular, posterior, occipital lymphadenitis. Forchheimer spots on soft palate appear before rash. Polyarthritis.
How is rubella diagnosed?
Confirm with serology or culture. Prevention: immunization with MMR vaccine.
What is the triad of roseola?
High fever preceding rash. Rose–colored papules on trunk. Occipital lymphadenopathy.
12–month–old infant with rash. Fever of 40 C. Fever resolved, then pink, slightly raised lesions on the trunk, upper extremities, face, and neck. What is the diagnosis?
Roseola
What is the cause of roseola?
Febrile illness caused by infection with human herpes virus: HHV–6; usually 6–15 months old; incubation period 5–15 days.
What is the clinical presentation of roseola?
High fever (up to 41 C) lasting a few days with symptoms of URI. Occipital lymphadenopathy. By the 3rd or 4th day, fever resolves and a maculopapular rash appears on the trunk, arms, neck, and face.
What are the characteristics of the rash of roseola?
Rose–colored rash begins as papules; treatment is supportive.
4–year–old child with swelling in his face and fever. Incomplete immunizations, tender facial swelling around the masseter muscle. What is the diagnosis?
Mumps
What is mumps?
Viral infection caused by Paramyxovirus transmitted by airborne droplets and respiratory and oral secretions in winter/spring. Incubation period 14–24 days. History of lacking immunizations.
What is the clinical presentation of mumps?
Fever, headache, and malaise. Salivary gland swelling, predominantly parotids. Arthritis; orchitis is rare before puberty; may result in sterility if bilateral.
How is mumps diagnosed?
Enzyme immunoassays for IgG and IgM for confirmation. Elevated serum amylase.
What is the treatment of mumps?
Treat orchitis with bedrest and testicular support. NSAIDs on steroids for severe arthritis.
What are the complications of mumps?
Meningoencephalomyelitis is the most common complication; pancreatitis, thyroiditis, myocarditis, deafness, and dacryoadenitis.
5–year–old with a fever of 38.8 C, pruritic rash in various stages of papules, vesicles, crusts. Began on trunk and spread to his extremities. What is the diagnosis?
Varicella
What is the cause of chicken pox?
Caused by varicella–zoster virus, a herpes virus. Incubation 10–21 days. Transmitted through respiratory secretions. Remains latent in sensory ganglia after recovery; reactivation in immunosuppressed.
What is the clinical presentation of varicella?
Mild abdominal pain and fever preceding pruritic rash in various stages. Macules then papules then vesicle and pustules. Lesions can turn hemorrhagic. Crops. Tzanck prep of lesion may reveal multinucleated giant cells.
What is the triad of varicella?
Rash in various stages. Crops. Pruritus.
What is the treatment for varicella?
Treat secondary infections. Consider acyclovir and VZIG in immunocompromised or if at risk for severe disease.
What are the complications of varicella?
Worse in adolescence and may cause scarring. Chickenpox pneumonia seen in 15–20%. Other sequelae include Guillain–Barre syndrome, encephalitis, cerebellar ataxia, post–herpetic neuralgia, and Ramsay–Hunt syndrome.
5–year–old with red slapped cheek appearance and a lacy rash on upper extremities and trunk. What is the diagnosis?
Erythema infectiosum (Fifth disease).
What is the cause of fifth disease?
Parvovirus B19, a DNA virus; seen most commonly in spring.
What is the clinical presentation of erythema infectiosum?
Mild systemic symptoms, arthritis, intensely red, slapped cheek” appearance. Lacy reticular rash over trunk and extremities; sparing of palms and soles; rash remains up to 40 days.”
How is fifth disease diagnosed?
Viral DNA in fetal blood is often helpful for diagnosing hydrops.
What are the complications of erythema infectiosum?
Aplastic crisis in patients with hemolytic anemia, such as sickle cell; erythroblastosis fetalis in neonates during maternal infection.
What is the triad of fifth disease?
Slapped cheeks”. Aplastic crisis. Fetal hydrops.”
What are the characteristics of the rash of fifth disease?
Slapped cheek, then to trunk, then central clearing to a lacy appearance.
What are the characteristics of the rash of varicella?
Crops of papules vesicles, crusts at same time; spreads centrally to peripherally.
What are the complications of scarlet fever?
Acute renal failure, glomerulonephritis.
What are the complications of varicella?
Superinfection of rash, zoster, pneumonia, hepatitis, encephalitis, congenital varicella.
What are the complications of measles?
Pneumonia, encephalitis, subacute sclerosing panencephalitis.
What are the complications of rubella?
Congenital rubella is teratogenic.
What is the complication of mumps?
Encephalitis, orchitis, pregnancy aqueductal stenosis; pancreatitis.
What is the complication of fifth disease?
Aplastic anemia.
What are the characteristics of the rubella rash?
Macules of face, neck, then trunk and extremities; posterior cervical and auricular lymphadenopathy. German measles.
What are the characteristics of the roseola rash?
Fever falls rapidly, then fine macular rash on trunk, which spreads to extremities.
What is the prodrome of scarlet fever?
Sore throat.
What is the enanthem of scarlet fever?
Exudative pharyngitis, strawberry tongue.
What are the characteristics of the rash in scarlet fever?
Fine maculopapular rash that feels like sandpaper, especially in antecubitus and inguinal areas; Pastia lines.
What is the exanthem of mumps?
Swollen parotid and submandibular glands.
23–year–old with fever, fatigue, sore throat. Generalized adenopathy most prominent in the anterior and posterior cervical nodes. What is the diagnosis?
Epstein–Barr virus.
What disease is caused by Epstein–Bar virus?
Infectious mononucleosis (90%)
What malignancies are associated with Epstein–Bar virus?
Nasopharyngeal carcinoma, Burkitt lymphoma; Hodgkin disease, lymphoproliferative disorders, and leiomyosarcoma in immunodeficiency states.
What is the mode of transmission for Epstein–Bar virus?
Transmitted in oral secretions by close contact (kissing disease); intermittent shedding for life. Incubation period 30–50 days; most cases in infants and young children are asymptomatic.
What is the clinical presentation of infectious mononucleosis?
Older child with insidious prodrome for 1–2 weeks with fever, fatigue, headache, myalgia, sore throat, abdominal pain.
What is the presentation of infections mononucleosis?
Lymphadenopathy (cervical submandibular; less often axillary, inguinal, epitrochlear nodes), splenomegaly. Pharyngitis with tonsillar enlargement, maculopapular rash occurs if treated with ampicillin or amoxicillin.
How is Epstein–Barr virus infection diagnosed?
Atypical lymphocytosis. Mild elevation in hepatic transaminases. Heterophile antibodies (Monospot test). IgM to viral capsid antigen is the most specific test.
What is the treatment for infectious mononucleosis?
No contact sports or strenuous activity with splenomegaly. Short course of steroids for airway obstruction, thrombocytopenia with hemorrhage, autoimmune hemolytic anemia, seizures, or meningitis.
What are the complications of Epstein–Barr virus infection?
Splenic hemorrhage or rupture (very rare) after trauma. Swelling of tonsils, causing airway obstruction. Guillain–Barre syndrome or Reye syndrome is rare, aplastic anemia, interstitial pneumonia, myocarditis.
What is the disease course in infectious mononucleosis?
Most cases resolve in 2–4 weeks; some disability that comes and goes for a few months is common; and there may be fatigue for a few years, but there is no evidence that EBV is related to chronic fatigue syndrome.
What is the triad of infectious mononucleosis?
Fatigue. Pharyngitis. Generalized adenopathy.
What infection is associated with a rash after taking ampicillin or amoxicillin for URI symptoms?
Infectious mononucleosis.
12–year–old girl with fever of 39 C, headache, sore throat, myalgia, chills and non–productive cough. What is the diagnosis?
Influenza
What are the causes of influenza?
Types: A, B, and C; A and B are the primary pathogens. Migratory avian hosts spread disease. Annual spread between Northern and Southern hemispheres; origin in Asia. 1 or 2 strains spread annually. Colder months. Transmission by aerosol.
What is the clinical presentation of influenza?
Predominantly respiratory illness. Abrupt onset with coryza, conjunctivitis, pharyngitis, and dry cough. Prominent systemic signs of fever, myalgia, malaise, headache.
How is influenza diagnosed?
Rapid diagnostic test with ELISA. Can be confirmed serologically with acute and convalescent titers. Virus can be isolated from nasopharynx early in course.
What is the treatment for influenza?
Antiviral drugs decrease severity and duration if administered within first 48 hours of symptoms. Oseltamivir, zanamivir.
What are the complications of influenza?
Otitis media, pneumonia; secondary bacterial infection, myocarditis.
What is the clinical presentation of AIDS in infants?
Rapid onset of symptoms and AIDS in first few months of life, lymphadenopathy, hepatosplenomegaly, failure to thrive, chronic diarrhea, interstitial pneumonia, oral thrush.
What manifestations of AIDS are more common in children than adults?
Recurrent bacterial infections, chronic parotid swelling, lymphocytic interstitial pneumonitis, early progressive neurological deterioration.
What is the category A classification of HIV infection?
Mild symptoms; at least two: lymphadenopathy, parotitis, hepatomegaly, splenomegaly, dermatitis, recurrent or persistent otitis media/sinusitis.
What is the category B classification of HIV virus infection?
Moderate symptoms: lymphocytic interstitial pneumonitis, thrush >2 m, chronic diarrhea, persistent fever >1 m, hepatitis, recurrent HSV stomatitis, esophagitis or pneumonitis, disseminated varicella, cardiomegaly, nephropathy.
What is the category C classification of HIV virus infection?
Severe symptoms: 2 serious bacterial infections in 2 y, esophageal/respiratory candidiasis, cryptococcosis, cryptosporidiosis, encephalopathy, malignancies, disseminated mycobacterial, PJP, cerebral toxoplasmosis, weight loss.
What infections occur in HIV–infected children?
Recurrent bacterial infections with encapsulated organisms and other gram–positive, gram–negatives. PJP, Mycobacterium avian complex: disseminated disease in severely compromised. Candidiasis, invasive fungal. Viral, herpes.
What are the non–infectious complications of HIV infection?
CNS disease, cardiomyopathy, enteropathy, wasting syndrome, nephropathy, cutaneous, manifestations, hematologic manifestations, malignancies.
How is HIV infection diagnosed in newborn children?
HIV–DNA by PCR. Maternal HIV IgG antibodies cross the placenta. Antibody screen will be positive in all newborns of HIV mothers up to 18 months of age. In any child >18 months of age: test for infection through IgG Ab by ELISA, confirm with Western blot.
What is the treatment of HIV in infants born to HIV–infected mothers?
Mother: perinatal triple antiretroviral therapy. Infant should be started on ZDV at birth until neonatal disease is excluded. Also start PCP prophylaxis (TMP–SMZ) at 1 month until disease excluded. CBC, platelets, CD4, CD8 counts.
What is ascariasis?
Ascaris lumbricoides; nematode (roundworm). Most prevalent human helminth in the world. High prevalence in poor countries with use of human waste as fertilizer and with geophagia.
What is the life cycle of Ascaris?
Travels to the small intestines then releases larvae then migrates through the venous circulation to the lungs and causes pulmonary ascariasis; enter through alveoli and bronchi to trachea and are swallowed to intestine to adult worms.
What is the clinical presentation of ascariasis?
Most are asymptomatic or mild. Most common symptom is cough and blood–stained sputum. Obstructive intestinal or biliary tract disease causing colicky abdominal pain or bile–stained emesis.
