Is severe visceral leishmaniasis a systemic inflammatory response syndrome? A case control study.
BACKGROUND
The objective of the study is to identify the main risk factors for death by New World visceral leishmaniasis and establish a coherent pathogenic substrate of severe disease based on clinical findings.


METHODS
Seventy-six deceased inpatients and 320 successfully treated inpatients with VL were studied in a case control study.


RESULTS
Bacterial infection and bleeding were mutually exclusive events leading to death. Five risk factors were unique for death by bacterial infection (malnutrition, pulmonary rales, severe anemia, severe absolute neutropenia and higher neutrophil count), while another six were unique for death by bleeding (jaundice, severe relative neutropenia, severe thrombocytopenia, liver injury, kidney failure, higher bone marrow parasite load). Bacterial infection, bleeding, severe anemia, diarrhea, dyspnea, edema, jaundice and bone marrow parasite load were the main syndromes of visceral leishmaniasis among successfully treated patients.


CONCLUSIONS
The data support the idea that bacterial infections are due to immune paralysis. Broad organ and system involvement is plausibly due to the high production of proinflammatory cytokines, whose actions fit well with visceral leishmaniasis. The syndromes and causative mediators are typical of a slowly developing systemic inflammatory response syndrome.
Costa
Carlos Henrique Nery
CH
Laboratory of Leishmaniasis, Tropical Diseases Institute Natan Portella, Teresina, PI, Brazil. chncosta@gmail.com
Werneck
Guilherme Loureiro
GL
Costa
Dorcas Lamounier
DL
Holanda
Thiago Ayres
TA
Aguiar
Guilherme Brasileiro
GB
Carvalho
Aline Santos
AS
Cavalcanti
Janaína Costa
JC
Santos
Loryenne Santos
LS
D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002423:Cause of Death; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007898:Leishmaniasis, Visceral / Q000401:mortality*; D008297:Male; D012307:Risk Factors; D012720:Severity of Illness Index; D018746:Systemic Inflammatory Response Syndrome / Q000401:mortality* / Q000469:parasitology; D055815:Young Adult