Where, when, and how the diagnosis of human visceral leishmaniasis is defined: answers from the Brazilian control program

BACKGROUND: Timely diagnosis is recommended by the Brazilian Visceral Leishmaniasis (VL) Surveillance and Control Program to reduce case fatality. Attempts at assessing this topic in Brazil are scarce. OBJECTIVE: This study aimed to describe where, when, and how the diagnosis of VL has been performed in a Brazilian endemic setting. METHODS: Data of all autochthonous cases confirmed between 2011 and 2016 (N = 81) were recorded. The care-seeking itinerary until the confirmation of VL diagnosis was assessed among 57 patients. FINDINGS: The majority of VL cases (79.1%) were reported by referral hospitals. The patients mainly sought primary health care centres at the onset of symptoms. However, they had to visit seven health services on average to achieve a confirmed diagnosis. The time from the onset of symptoms to the diagnosis of VL (T(D)) ranged from 1-212 (median, 25) days. The T(D) was longer among adult patients. There was a direct correlation between the patient’s age and T(D) (r = 0.22; p = 0.047) and a higher occurrence of deaths due to the disease among older patients (p = 0.002). Almost all the patients (98.9%) underwent laboratory investigation, and the VL diagnosis was mainly confirmed based on clinical-laboratory criteria (92.6%). Positive results for the indirect fluorescence antibody test (22.7%) and parasitological examination plus rk39-based immunochromatographic tests (21.3%) were commonly employed. MAIN CONCLUSIONS: VL diagnosis was predominantly conducted in hospitals with a long T(D) and wide application of serology. These findings may support measures focused on early diagnosis, including a greater involvement of the primary health care system.