Early Candida parapsilosis Sepsis Detection Using Sysmex XN-3000 Hematological Analyzer: Case Report

    

    

    Figure 2: Cumulative differencial scattergram showing the erythroblast canal (NRBC) suspected of Candida sp.
    

Thus, although asymptomatic, an early diagnosis of invasive fungal infection was done and started antifungal therapy with Amphotericin B, followed by lock therapy, what was maintained for 14 days after culture negativity. In parallel to use antifungal agent, the Hickmann catheter was changed and three mother donor granulocyte infusions were performed.

Despite to the fact that patient persisted for a long time with febrile neutropenia, no evidence of another infectious disease was found. Patient also presented BCG infection and pulmonary mycobacteriosis, acute grade I Graft versus Host Diesease, which were managed as usual in the HSCT scenario.

Discussion

The detection of Candida species in peripheral blood smears suggests advanced disseminated infections with uncontrollable complications, whether they were detectable or not in clinical examinations, caused by the burden of Candida species in the blood, which is indicative of poor prognosis. In case of candidemia, an etiological treatment must be started only after a positive blood culture. As microbiological testing requires some days to be fully performed and sepsis mortality is increased by any delay in diagnosis and treatment, in some patients the benefit of starting an early empiric antifungal treatment based on the available clinical and laboratory data often outweigh any other risk.

La Gioia et al. described two cases were the presence of distinctive alterations in the 3D-DIFF cytograms could be characteristic of the presence of Candida sp. in the sample. They presented blood cell count performed on BC-6800 hematological analyzer (Mindray, Shenzhen, China). In hematological analyzers, the circulating leukocytes as well as erythroblasts are evaluated by side and forward laser scatter (SS and FS) and by Fluorescence (FL). The resulting Three-Dimensional (3D) scattergram can be rotated to allow a detailed observation of cell population clusters, their complexity, size and nucleic acids cell content [2]. Small size and low internal complexity form a plankshaped cloud, suggestive of yeast infestation, regardless of number. Besides that, neutrophil population may present extension in FC/SS axis, evidencing increase in the size and internal complexity, which occurs when there is yeast phagocytosis by neutrophils. The prompt microscopic review can confirm the presence of circulating fungal pathogen.

In the present case, the viewed of a blue cloud in NRBC channel different from the common pattern found for these cells on the XN-3000 hematology analyzer cytogram allowed us to suspect the presence of Candida sp. in the sample, later confirmed by blood culture. This fact allow early iniciation of antifungal therapy and probably, prevented baby´s death.

Conclusion

Our observations suggest that NRBC cytograms generated by the automatic analyzers may be useful for early diagnosis of Candida sp., enabling to anticipate antifungal therapy, e possible reducing mortality rate of immunosuppressed and HSC transplanted patients.

References

1. Devrim I, Yaman Y, Demirag B, Oymak Y, Carti Ö, Özek G, et al. A single center’s experience with Candida parapsilosis related long-term central venous access device infections: the port removal decision and its outcomes. Pediatr Hematol Oncol. 2014; 31: 435–441.
2. Hirai Y, Asahata S, Ainoda Y, Fujita T, Miura H, Hizuka N, et al. Candidemia diagnosed from peripheral blood smear: case report and review of literature 1954–2013. Mycopathologia 2015; 180: 111–116.
3. La Gioia A, Bombara M, Fiorini F, Dell’Amico M, Devito A, Isola P, et al. Earlier detection of sepsis by Candida parapsilosis using three-dimensional cytographic anomalies on the Mindray BC-6800 hematological analyzer. Clin Chem Lab Med. 2016; 54: e239–e242.