gms | German Medical Science

Introduction: We describe three cases of acute disseminated Histoplasma capsulatum infection in pediatric patients with Acute Lymphoblastic Leukemia (ALL) (see Table 1 [Tab. 1]). One of these patients concurrently experienced haemophagocytic lymphohistiocytosis syndrome (HLH) caused by Histoplasma capsulatum, which is the first reported case of HLH secondary to histoplasmosis infection in a pediatric patient with ALL. Cases of HLH secondary to histoplasmosis in immunocompromised adult patients with CML, AIDS, and kidney transplant recipients and a child with Chronic Mucocutaneous Candidiasis have been previously described [1] [2] [3].

Table 2 [Tab. 2] provides details of the acute disseminated histoplasmosis in these children.

Discussion: All 3 were patients with B-cell ALL and were in maintenance phase of therapy. Prolonged fever (1 with respiratory symptoms), neutropenia, and mild elevation in transaminases were common to all three patients. All 3 had PCR tests negative for multiple viruses except the patient with HLH who had Parainfluenza 3 isolated from a nasopharyngeal specimen.

Diagnosis of Histoplasmosis was confirmed by bone marrow histology in two patients and on BAL for the one patient with pulmonary histoplasmosis.

All 3 had multiple positive blood cultures and positive urine histoplasma antigen assay However, serum antibody testing was negative in all, which has been noted previously in patients with malignancy [4].

Lipid formulation of amphotericin and itraconazole sequential therapy were effective treatmen. Patient 2 experienced severe Vincristine toxicity with itraconazole [5]. The patient with HLH received 2 weeks of dexamethasone for treatment of HLH in addition to antifungal therapy. Declining serum ferritin levels served as a therapeutic marker.

All three of the patients experienced positive clinical outcomes with declining antigenuria.

Conclusion: In an endemic area clinicians should be aware of the possibility of disseminated histoplasmosis and of secondary HLH in pediatric cancer patients with fever of unknown origin and pancytopenia, to avoid delay in diagnosis and the risk of increased morbidity.