Tickborne Relapsing Fever Diagnosis Obscured by Malaria, Togo

Abstract

Given the prevalence of relapsing fever (RF) in Senegal, this disease may cause illness and death in other areas of West Africa. We performed a cross-sectional, clinic-based study to investigate the presence of RF in Togo during [2002][2003][2004]. Blood samples from patients with fever were examined for RF spirochetes by microscopy, PCR, and DNA sequencing of amplicons and for antibodies to the glycerophosphodiester phosphodiesterase antigen. Although no spirochetes were seen in blood smears, ≈10% of the patients were positive by PCR and ≈13% were seropositive for spirochetes. DNA sequencing demonstrated that Borrelia crocidurae and B. duttonii were present. Most patients were treated for malaria whether or not plasmodia were observed. Thus, many RF patients originally had a misdiagnosis of malaria, which resulted in ineffective treatment. The inability of microscopic analysis to detect spirochetes compared with PCR demonstrates the need for tests with greater sensitivity.

Concomitant Infection Decreases the Malaria Burden but Escalates Relapsing Fever Borreliosis

“…It is possible that other infections, such as bacterial diarrheal illnesses, are underreported and might exceed the incidence of RF. To further complicate diagnosis, some patients may have malaria/RF coinfection, as was the case for 4.5% of the febrile patients in our investigation in Togo (21), and comparable findings have also been recorded in Ethiopia and Senegal (23,26). Due to the similarity of clinical symptoms and common use of presumptive diagnostics, there is no doubt that misdiagnosis and inappropriate medication of RF often occur, as well as frequent concomitant infections.…”

“…Considering that the most prominent symptom of malaria is fever (4) and that the WHO advises that a presumptive malaria diagnosis be made in areas where malaria is endemic, it is plausible that misdiagnoses can be made in patients who are not suffering from malaria or who have a concomitant infection (14). This assumption is supported by the results of a field study conducted by our research team in Togo, West Africa, in which 8.8% of febrile patients diagnosed as having malaria were subsequently found to have relapsing fever (RF) borreliosis, which is caused by spirochete bacteria of the genus Borrelia (21). This could be simply due to incorrect malaria diagnosis, which is plausible since both Plasmodium and RF Borrelia cause systemic infections with similar manifestations that involve recurrent fever, anemia, and hepatosplenomegaly.…”

“…Malaria and RF occur in the same geographical areas and have been detected as coinfections in fever patients (21,23,26). We developed a mouse model using P. berghei and B. duttonii to study the host-pathogen interactions in simultaneous malaria/RF infection.…”

Relapsing Fever Borreliae in Africa

“…; this classification was based on a cospeciation hypothesis that postulated that only one relapsing fever Borrelia species could be found in a particular host and vector in a given geographic area. However, recent demonstrations of the coexistence of B. duttonii and B. crocidurae in Togo 35 and of B. crocidurae and B. hispanica in North Africa 36 suggest that the previous geographical distribution studies were not comprehensive. Further microscopic observation of relapsing fever borreliae isolated from vectors and the blood of patients after Giemsa staining did not help to distinguish the species, nor did observations of characteristic morphology and motility by dark field microscopy, phase contrast microscopy, and electron microscopy.…”

“…The MST can achieve this goal because sequencing both the glpQ gene and RELAPSING FEVER BORRELIAE the IGS is suitable for differentiating B. crocidurae and B. hispanica from B. duttonii and B. recurrentis, as illustrated in samples from Morocco and Tunisia. [26][27][28][29][30][31][32][33][34][35][36][37][38][39] Conventional PCR with or without sequencing and real-time PCR targeting these genomic regions have been used to document borreliae in reservoirs, ectoparasites, and clinical specimens. [43][44][45][46] Relapsing fever borreliae with cultured representatives in Africa.…”