Severe Visceral Leishmaniasis Associated With COVID-19 and Complicated by Hemophagocytic Syndrome.

Abstract

To the Editors: Visceral leishmaniasis (VL) is a parasitic infectious disease that mainly affects children. if neglected the disease could become systemic.1 Coronavirus disease 2019 (COVID-19) is a viral disease that could complicate the management of several infectious diseases in different regions worldwide.2 Managing severe pediatric VL associated with COVID-19 and complicated by hemophagocytic syndrome (HPS) as well as finding an efficient therapeutic protocol to reduce mortality is a challenge. VL associated with HPS and COVID-19 have not been reported previously; therefore, a report of a case with a favorable outcome is extremely important. We present the case of a pediatric patient with VL complicated with HPS and associated with COVID-19. A 9-month-old infant, female, living in the northeastern region of Brazil was admitted caused by intermittent fever, vomiting after feedings, weight loss, and abdominal distention. Further investigations revealed pancytopenia with severe neutropenia and anemia, hypoalbuminemia, hepatosplenomegaly, hypertriglyceridemia, hypofibrinogenemia, high ferritin level, and urosepsis. Chest radiography showed diffuse perihilar infiltrates. A myelogram revealed numerous isolated forms of Leishmania sp. and hemophagocytosis figures. After severity score testing, the patient was diagnosed with severe VL complicated by HPS, and was treated with liposomal amphotericin B, corticoid, and human immunoglobulin. The patient developed acute respiratory failure, and reverse-transcriptase polymerase chain reaction (RT-PCR) for COVID-19 tested positive. The patient subsequently developed a renal injury, septic shock and coagulopathy, and required pediatric intensive care with invasive ventilation, peritoneal dialysis, vasoactive drugs and blood products. After 13 days of intensive care, clinical improvement was observed and the patient was transferred to the ward. The patient’s general clinical status improved; hence, the patient was discharged and followed up as an outpatient with favorable outcomes (Figure 1).FIGURE 1.: Diagram showing how the combination of Leishmania and SARS-CoV-2 led to HPS. HPS indicates hemophagocytic syndrome.HPS associated with VL is well known.1 The uniqueness of this case report is the pulmonary involvement of COVID-19, which increased its severity. Further, liposomal amphotericin B treatment was extended to 14 doses because of persistent clinical and laboratory signs of VL and symptoms of COVID-19; however, the Brazilian protocol prescribes 7 doses. VL is an immune-mediated disease that mainly affects children caused by their immature cell-mediated immunity. The amastigotes of the parasite multiply inside macrophages and subsequently spread through the blood to the lymph nodes, liver, spleen and bone marrow. This leads to uncontrolled activation of T lymphocytes, natural killer cells and macrophages, and could increase the levels of proinflammatory cytokines and lead to HPS.3 Generally, the clinical features of VL overlap with those of HPS. Regarding the COVID-19/HPS association, the immune syndrome induced by COVID-19 is not yet fully understood; however, the presence of an inflammatory response is certain.4 Another condition that is associated with COVID-19 is pediatric multisystemic inflammatory syndrome, which presents with inflammatory response with clinical and laboratory changes that can mimic HPS.5 Delayed diagnosis of HPS associated with VL, probably because of clinical similarities, may result in severe complications and death in up to 90% of untreated cases.6 The association of VL, HPS and COVID-19 have not been described in the literature; therefore, dissemination of this case report is fundamental, as it highlights the importance of therapeutic, clinical and epidemiological management.