Hidden in plain sight: urinary Cryptococcus neoformans missed by routine diagnostics in a patient with acute leukemia.

Cryptococcuria is a rare manifestation of localized cryptococcal disease. We present a case of Cryptococcus neoformans urinary tract infection in an immunocompromised host missed by routine laboratory workup. The patient had negative blood cultures, a negative serum cryptococcal antigen (CrAg), and "non-Candida yeast" growing in urine culture that was initially dismissed as non-pathogenic. The diagnosis was ultimately made by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) from a repeat urine culture after transfer to a tertiary care center. Cryptococcus should be considered in the differential of refractory urinary tract infections growing non-Candida yeast.

Use of triazoles for the treatment of invasive aspergillosis: A three-year cohort analysis.

In a 3-year cohort study of adult patients with proven or probable IA, fewer patients initially treated with isavuconazole experienced adverse events compared with voriconazole, but more patients required a change in therapy due to lack of clinical efficacy.

Three Cases of Neurologic Syndrome Caused by Donor-Derived Microsporidiosis.

In April 2014, a kidney transplant recipient in the United States experienced headache, diplopia, and confusion, followed by neurologic decline and death. An investigation to evaluate the possibility of donor-derived infection determined that 3 patients had received 4 organs (kidney, liver, heart/kidney) from the same donor. The liver recipient experienced tremor and gait instability; the heart/kidney and contralateral kidney recipients were hospitalized with encephalitis. None experienced gastrointestinal symptoms. Encephalitozoon cuniculi was detected by tissue PCR in the central nervous system of the deceased kidney recipient and in renal allograft tissue from both kidney recipients. Urine PCR was positive for E. cuniculi in the 2 surviving recipients. Donor serum was positive for E. cuniculi antibodies. E. cuniculi was transmitted to 3 recipients from 1 donor. This rare presentation of disseminated disease resulted in diagnostic delays. Clinicians should consider donor-derived microsporidial infection in organ recipients with unexplained encephalitis, even when gastrointestinal manifestations are absent.

Immune Control in Repeated Babesia microti Infection in a Patient With B-Cell Deficiency.

The immunology of human babesiosis is poorly investigated. We present a comprehensive investigation of a 75-year-old man with B-cell deficiency who experienced 3 episodes of babesiosis over a 6-year period. Slowly evolving clinical immunity was observed, as evidenced by milder clinical symptoms and lower peak parasite burden after each subsequent babesiosis episode. The patient exhibited several striking immunologic findings. First, the patient had exceptionally high Babesia microti-specific antibodies despite very few circulating B cells, which predominantly coexpressed CD27 (memory marker) and CD95 (death receptor). Second, we demonstrated the presence of long-lasting NK cells and expansion of T memory stem cells. Third, levels of the IP-10 cytokine directly correlated with parasite burden. These results raise fundamental questions on the priming, maintenance, and location of a B-cell population that produces high antibody levels in the face of severe B-cell deficiency. Our results should invoke interest among researchers to study the immunology and pathogenesis of human babesiosis.

An Avid Imitator.

We present a case of disseminated cryptococcal disease, coexisting with and mimicking lymphoma. Determination of serum cryptococcal antigen should be considered for lymphopenic patients with hematologic malignancies, presenting with unexplained fever, and/or lymphadenopathy and/or pulmonary findings. Patients with hematologic malignancies treated with chemotherapy regimens are susceptible to diverse opportunistic infections. Therefore, in this patient population, it is often necessary to obtain a definitive pathologic diagnosis, to diagnose uncommon syndromes and guide management.