Gastrointestinal symptoms, respiratory, hepatic and renal dysfunction, main factors associated with lethality due to tickborne rickettsiosis in Mexicali, Baja California, Mexico.

Abstract

Background: Rickettsiosis, a potentially fatal disease, is transmitted by vectors such as Rhipicephalus sanguineus, Dermacentor variabilis and D. andersonii, reservoirs of Rickettsia rickettsii. In Baja California, Mexico, it is endemic, multifactorial, has high lethality, its nonspecific clinical manifestations and multisystem attack make diagnosis and timely treatment difficult. Aim: Identify the risk factors associated with lethality due to tick-transmitted rickettsiosis in Mexicali, Baja California. Methods:. Observational, analytical, cross-sectional, retrospective study of 40 records of patients with a confirmed diagnosis of rickettsiosis, period 2014 to 2018. Analyzed variables: sociodemographic, clinical, clinical laboratory, evolution and outcome. Frequencies and association measures are reported.. Results: 24 patients died and 16 survived. More than 90% had contact with ticks. It mostly affected <45 years in both groups. The evolution before admission was similar, and the hospital stay was longer in patients who lived (3.2+4.7 vs 10.62+7.6 p=0.0002). Fever, headache, and myalgia are predominant. Data associated with lethality: respiratory dysfunction (OR 38.33 95% CI 4.06-361.3 p<0.0001), elevated creatinine (OR 15.4 95% CI 3.08-76.77 p<0.0003), delayed capillary refill (OR 13.0, 95% CI 2.73-61.78 p=0.0005), abdominal pain (OR 8.33, 95% CI 1.90-36.44 p=0.0029), AST (OR 7.5, 95% CI 1.69-33.27 p=0.005). Conclusion: This disease requires early identification of factors that are associated with lethality for timely and adequate treatment.