June 17, 2014 Grand Rounds

Case 1: 73 year old man with neutropenia secondary to chemotherapy for a recent diagnosis of AML who presents with acute onset appearance of diffuse skin nodules and fever secondary to Fusarium sp.

1. Always think of disseminated Candida and Fusarium infection in a neutropenic patient who presents with sudden onset skin nodules and fever.

2. We usually treat serious Fusarium infection with amphotericin plus voriconazole. This is because different species of Fusarium may display different susceptibility patterns. For example. Fusarium solani and Fusarium verticilliodes are azole-resistant while Fusarium oxysporum and Fusarium moniliforme are usually susceptible to either voriconazole or posaconazole.A good review of Fusarium infection in immunocompromised patients can be found here.

3. The greatest risk factor for mortality secondary to Fusarium infection is persistent neutropenia.

Case 2: 7 month old infant who presented with fever, morbiliform rash, acute mental status change, and seizure secondary to vanishing white matter disease.

1. The discussion centered on why measles was unlikely in this case (i.e. vaccination was up to date, measles Ig M was negative, rash preceding onset of fever).

2. The discussion also talked about measles encephalitis. It commonly develops during the viral exanthem or within 8 days of illness onset. Around 51% of patients with measles may have EEG abnormalities in the absence of actual encephalitis. Patients with measles may also have a CSF with <10 cells (15%).

3. Vanishing white matter disease, caused by specific genetic abnormalities, is characterized by gradual disappearance of the white matter after an initial normal development.

Case 3: 49 year old man with diffuse lymphadenopathy, hepatosplenomegaly, fever, constitutional symptoms, and necrotizing granulmatous lesions on bone marrow biopsy

1. Differential diagnoses are broad: tuberculosis, fungal infection, Q fever, bartonellosis, syphilis, lymphoma, et al. A good review is found here.

2. In this patient, multiple cultures failed to isolate an infective agent. Biopsy smears were also negative. In this situation, further tissue biopsy should be done as lymphoma can sometimes be difficult to diagnose.

3. Necrotizing granulamotous disease in a sick patient may warrant empiric anti-tuberculosis treatment while waiting for culture results.