Snapshot A 24-year-old non medical compliant HIV male patient presents with odynophagia. Upon inspection of the oropharynx white, scrapable exudates are seen that are bleeding when perturbed. Candida Albicans Diseases in normal hosts oral thrush inhaled corticosteroids (e.g. in treatment of asthma) predispose candida intertrigo (skin folds) vaginitis diaper rash perleche (angular cheilitis) cracks at the corner of the mouth seen in malnutrition in immunocompromised (especially AIDS or neutropenic) esophagitis thrush spreads down GI tract endocarditis in IV drug users septicemia due to indwelling catheters (e.g., subclavian catheter) disseminated candidiasis chronic mucocutaneous candidiasis local infection is due to T-cell deficiency while systemic infection is due to neutropenia Pathogenesis normal flora → opportunistic infection Laboratory yeast with pseudohyphae and budding at 20°C germ tube formation at 37°C (diagnostic) true hyphae sprout from yeast and are seen on light microscopy Treatment nystatin for superficial infection amphotericin B for systemic infection fluconazole for vaginal candidiasis empiric azole or echinocandin therapy for immunocompromised patients with esophagitis Snapshot A 40-year-old patient with a CD4+ cell count of 27 presents with a headache, fever, and neck stiffness. The patient has not been compliant with his medications and states the symptoms came on gradually. Lumbar puncture is performed and an India ink stain is applied and seen to the right. Cryptococcus Neoformans Diseases meningitis in AIDS (most common meningitis) in Hodgkin's disease (most common meningitis) "soap bubble" lesions in brain can also cause encephalitis pneumonia seen in pigeon breeders skin and bone infections Pathogenesis transmitted via pigeon droppings yeast spreads hematogenously to brain 75% of cases in immunocompromised Laboratory polysaccharide capsule wide capsular halo can be seen the only pathogenic fungus with a polysaccharide capsule unequal budding with narrow base monomorphic culture on Sabouraud's agar urease positive yeast stains with India ink mucicarmine stains red methenamine silver (GMS) is also used latex agglutination test detect polysaccharide capsular antigen in CSF Treatment amphotericin B + flucytosine 10 weeks followed by fluconazole serial LP's to reduce ICP Snapshot A patient with a past medical history of asthma presents with recent onset worsening of asthma symptoms and coughing up of brown mucous plugs. A CT scan is performed demonstrating the findings to the right and serum IgE levels and eosinophils are elevated. Aspergillus Diseases, pathogenesis, and treatment inhalation of ubiquitous Apergillus spores causes 3 diseases allergic bronchopulmonary aspergillosis asthma-like allergic reaction in airways proximal bronchiectasis type I and type IV hypersensitivity reactions mucus plugs form but do not penetrate tissue treatment systemic corticosteroids and oral itraconazole aspergilloma seen in TB patients (or other granulomatous disease) "fungus ball" forms in pre-existing lung cavities treatment surgery invasive aspergillosis invasive infection of the lung usually in immunocompromised pleuritic pain, hemoptysis infiltrate seen on radiograph and CT treat with strongest antifungals including voriconazole, amphotericin B, or caspofungin Toxins aspergillus produces aflatoxin causes liver damage and liver cancer aflatoxin B1 causes G:C -> T:A mutation in codon 249 of p53 increased risk of hepatocellular carcinoma Laboratory monomorphic septate hyphae branch at acute angles "ASpergillus is Acute and Septate" fruiting bodies are rare a recycler (found in compost piles) catalase-positive Snapshot A diabetic patient presents with facial and periorbital pain, as well as a headache and purulent nasal discharge that has rapidly progressed. A biopsy performed reveals non-septate hyphae that branch at wide angles. Mucor, Rhizopus Diseases rhinocerebral infection (mucormycosis) frontal lobe abscesses paranasal swelling hemorrhage from nose and eyes fungi also penetrate blood vessel walls results in infarction and necrosis Pathogenesis spores found in soil fungus penetrates through sinuses into brain seen in acidotic patients diabetic ketoacidosis leukemia Laboratory irregular non-septate hyphae branch at wide angles filamentous Treatment amphotericin B (must act quickly) surgical debridement