A 58-year-old Caucasian male was diagnosed in early 2014 with multiple myeloma. He was treated with dexamethasone, cisplatin, doxorubicin, cyclophosphamide, and etoposide-induction chemotherapy and then tandem ASCT in June and September 2014, respectively. Pretransplant chemotherapy consisted of bortezomib, dexamethasone, thalidomide, and melphalan 200 mg/m2 (VDT-Mel). Prior to HSCT, the recipient was seropositive for T. gondii. Antimicrobial prophylaxis consisted of fluconazole, acyclovir, and ciprofloxacin. He developed low-grade fevers, headaches, and impaired memory following engraftment on day +17 after second transplant.
A new thalamic lesion with edema and mass effect on the third ventricle and faint peripheral enhancement was found on a contrasted brain magnetic resonance imaging (MRI). Blood cultures were negative. CSF (cerebrospinal fluid) demonstrated elevated protein, normal glucose, and a WBC count 94/microL with predominantly lymphocytes (62) and histiocytes (32). Cytology showed no tumor cells. Cerebrospinal fluid (CSF) demonstrated elevated protein (245 mg/dl), normal glucose (48 mg/dl), and a WBC count 94/microL with predominantly lymphocytes (62/microL) and histiocytes (32/microL). Cytology showed no tumor cells. CSF bacterial and fungal cultures, cryptococcal antigen assay, herpes simplex virus, enterovirus, human herpes virus 6, Ebstein-Barr virus, and JC virus polymerase chain reactions (PCRs) were negative. HIV screen (antigen/antibody testing), fungal serologies, and Quantiferon-TB Gold were negative. CSF and serum toxoplasma PCR were positive. The patient was neutropenic (ANC < 500/microL) for approximately seven days following both transplants, but lymphopenia lasted for a prolonged period.
The patient was empirically started on sulfadiazine and pyrimethamine with leucovorin. He developed crystal nephropathy with renal failure while on sulfadiazine and was changed to clindamycin and pyrimethamine for 8 weeks. Response to treatment was favorable at 1-month follow-up, as assessed by clinical and radiological means. Subsequently, he was switched to pyrimethamine, leucovorin, and atovaquone as secondary prophylaxis for toxoplasma infection while he was lymphopenic during ongoing maintenance chemotherapy. The patient died 30 months after HSCT due to progressive myeloma with no evidence of toxoplasmosis.