Fatal Brazilian spotless fever caused by Rickettsia rickettsii in a dark-skinned patient

Abstract

Brazilian spotted fever (BSF) is the most important and frequent rickettsial disease in Brazil. A fatal case of BSF is reported in a 32-year-old black man, who died of irreversible shock after five days of fever, severe headache and abdominal pain with no rash. Spleen, kidney and heart samples collected at autopsy were positive for Rickettsia rickettsii by PCR and sequencing. The authors emphasize the need for a high index of diagnostic suspicion for spotted fever in black patients. Absence of a skin rash should not dissuade clinicians from considering the possibility of BSF and initiating empirical therapy.

Comparative value of blood and skin samples for diagnosis of spotted fever group rickettsial infection in model animals

“…If this is true, then the ear should also be the most opportune site for detection of rickettsial DNA in other domestic and wild animals. At the same time, SFG rickettsiae are often found in internal organs collected postmortem from guinea pigs (this study), as well as from dogs (Levin et al, 2014) and humans (Walker et al, 1983; Walker and Gear 1985; Favacho et al, 2011). In dogs infected with either R. conorii or R. rickettsii , widespread abundant petechiae on gums and buccal mucosa developed in parallel with macular skin rash (Levin et al, 2012, 2014).…”

“…Molecular biological methods have the potential to expedite specific diagnosis of infection and rickettsial DNA have been successfully detected in eschar tissue or eschar swabs of patients with several SFG rickettsioses (Lakos 2002; Wang et al, 2009; Bechah et al, 2011; Mouffok et al, 2011; Myers et al, 2013) or in biopsies of a skin rash (Kuloglu et al, 2012; Denison et al, 2014). However, R. rickettsii infections are rarely accompanied by an eschar (Walker et al, 1981; Chen and Sexton 2008), and a typical skin rash may not appear until later stages of illness, or not at all (Walker 1989; Sexton and Corey 1992; Favacho et al, 2011). To date, there are no published studies assessing usefulness of skin biopsies not associated with eschars or sites of tick attachment for detection of SFG pathogens in either humans or animals.…”

An update on the epidemiological situation of spotted fever in Brazil

“…The most affected ethnic group in Brazil was white people, especially in the Southeast and South. However, rash is not easily seen in black complexion and this could be hindering the diagnosis of SF cases in this ethnic group [30]. …”

Febre Maculosa No Brasil: Situação Epidemiológica Atual E a Distribuição Geográfica De Carrapatos Em Cenários De Mudanças Climáticas

“…O exantema maculopapular (Figura 1), embora tenha grande importância na identificação de casos suspeitos, pode vir a ser um evento tardio, podendo se manifestar até o 5º dia após o início de sintomas; tal retardo pode, eventualmente, resultar em atraso no diagnóstico, já que a suspeita clínica seria prejudicada, determinando início tardio do tratamento específico e consequente risco de prognóstico desfavorável (Chapman et al, 2006;Favacho et al, 2011;Ministério da Saúde do Brasil, 2016a).…”

“…A ausência da introdução da terapêutica antimicrobiana específica, em tempo oportuno, pode resultar na progressão do quadro clínico com complicações que incluem acometimento neurológico, insuficiência respiratória, insuficiência renal, hipotensão e choque (Chapman et al, 2006;Angerami et al, 2006;Angerami et al, 2009;Favacho et al, 2011;FacciniMartínez et al, 2014;Ministério da Saúde do Brasil, 2016a (lesão no local onde o carrapato fica aderido) e a linfadenopatia (Paddock et al, 2004;Spolidorio et al, 2010;Silva et al, 2011;Faccini-Martínez et al, 2014;Krawczak et al, 2016a (Chapman et al, 2006; Ministério da Saúde do Brasil, 2016a).…”