Re-emerging paracoccidioidomycosis in Argentina with peculiarities in the diagnosis and clinical manifestations

GIUSIANO G; CATTANA ME; TRACOGNA F; SOSA MA; ROJAS F; FERNÁNDEZ M; CECH N; ARECHAVALA A

Lisboa

Congreso; 7th Trends in Medical Mycology; 2015

European Confederation of Medical Mycology (ECMM)

Paracoccidioidomycosis (PCM) is a systemic endemic mycotic disease caused by the thermally dimorphic fungus Paracoccidioides. The fungus has a geographic distribution limited to tropical and subtropical areas from rural areas of Central and South America. PCM is the commonest systemic mycosis in Latin America without mandatory reporting and considered as a Neglected Disease.Argentina has two endemic areas of PCM; the more extensiveis located in the northeast near Paraguay and Brasil, where the chronic PCM is the historically observed clinical form.In the last years, an increase of the PCM incidence associated with urban cases, patients with rare clinical manifestations or infrequent locations and also, cases of juvenile PCM never described before in that area was observed. In addition, a high percentage of negative serological diagnosis was detected both in chronic and juvenile clinical forms.In order to know the status of the current clinical and epidemiological characteristics of PCM in Argentina, a multicentric study of PCM coordinated by Departamento Micología of Instituto de Medicina Regional of Universidad Nacional del Nordeste (Argentina) was started.We present a retrospective descriptive analysis of PCM cases from 2013 to 2015.A total of 67patients with PCM, aged 13 to 89 years (median 49 years) were recorded. In 2013 were recorded 23 cases, 32 in 2014 and 12 cases only from January to April 2015, pointingthe annual increasing.A lower male/female relationship (12:1) than reported by others countries was observed.Chronic form in 63 patients and juvenile PCM in 4 patients were recorded. Without classical manifestations that suggest PCM, about 15% of patients only showed rare manifestations or infrequent locations such as osteomyelitis, cerebral and cerebellar abscesses, cutaneous lesions, that delayedthe diagnosis. Clinical manifestations observed in all patients are presented in Table 1.Serological and microbiological diagnosis was achieved in 46 patients, in 6 patients only serological and only microbiological in 15 cases. Negative serological resultswith microbiological diagnosisin 9 cases (13%) were obtained.The knowledge that Paracoccidioides includes P. lutzii and P. brasiliensis with cryptic species can be an explanation for this finding. Although the impact of this genotypic diversity is not completely understood, data suggest that false negative results could be obtained with the standard immunodiffusion test performed using the Gp43 antigen of P. brasiliensis B 399 strain in patients infected with a strainthat hasdifferent antigenic profile.Several unexplained peculiarities have been noted in the diagnosis and clinical manifestations. The recognition of the re-emergence of PCM in Argentina with particular characteristics requires urgent research to explore specifically the circulating Paracoccidioides species in order to improve the diagnosis and therapeutic tools.