Risk Factors Associated with Life-threatening Rickettsial Infections

Abstract

We retrospectively analyzed 92 cases of severe rickettsial infections in patients (median age = 49 years, 57% male, 37.0% with scrub typhus) in Hong Kong. Immunofluorescence assay was used for diagnostic confirmation. Identification of > or = 1 diagnostic sign (exposure history, rash, or eschar) was possible in 94.6% of the cases. Multivariate analysis suggested that pulmonary infiltrates (odds ratio [OR] = 25.2, 95% confidence interval [CI] = 3.9-160.9, P = 0.001) and leukocytosis (OR = 1.3, 95% CI = 1.0-1.5 per unit increase, P = 0.033) were independent predictors of admission to an intensive care unit (14.1%). Delayed administration of doxycycline was independently associated with major organ dysfunction (23.9%; oxygen desaturation, renal failure, severe jaundice, encephalopathy, cardiac failure) (OR = 1.2, 95% CI = 1.0-1.5 per day delay, P = 0.046; adjusted for age and rickettsia biogroup) and prolonged hospitalization > 10 days (25%) (OR = 1.4, 95% CI = 1.1-1.9 per day delay, P = 0.014). Treatment with fluoroquinolone/clarithromycin did not correlate with clinical outcomes (P > 0.05). Early empirical doxycycline therapy should be considered if clinico-epidemiologic signs of rickettsial infections are present.

Caso fulminante de rickettsiosis (Rickettsia rickettsii) en una lactante del sureste de México

“…1,14 Cabe destacar que existen estudios que confieren valor pronóstico a los estudios paraclínicos en conjunto con los datos clínicos, en función del daño orgánico que reflejan; en este caso, la leucocitosis, datos de compromiso cardíaco y renal, edad pediátrica, admisión a la UCIP y retraso mayor de 4 días para iniciar el tratamiento son condiciones asociadas a mortalidad. 14,15 Este caso permite reivindicar que, en nuestro medio, la RMSF es una enfermedad circulante, no limitada al área rural o selvática, que puede presentar un curso clínico grave y, por lo tanto, debe considerarse dentro de los diagnósticos diferenciales en pacientes con síndrome exantemático febril y antecedentes epidemiológicos relevantes. Además, su homología con series de casos ya reportadas resalta la necesidad de contar con capacitación continua para los médicos de primer contacto, sobretodo en regiones conurbanas y rurales, en busca de reducir las cifras de mortalidad.…”

Scrub Typhus with Sepsis and Acute Respiratory Distress Syndrome

“…The patient did not respond to quinolone and macrolide therapy. Scrub typhus is well known to be unresponsive or show only a suboptimal response to quinolones, beta-lactams, penicillins, clarithromycin, and cephalosporins (8,16,17), and in northern Thailand, there has been a reported case of resistance to chloramphenicol and doxycycline (18). It is also notable that the Widal, Weil-Felix test, a generally used diagnostic test for rickettsial diseases, showed a negative result with the patient sample.…”

Aftermath Earthquake in Nepal: Burden of Scrub Typhus Cases and their Presentations

“…The early manifestations are an eschar, representing localized cutaneous necrosis at the site of mite feeding (which is not always present) and regional lymphadenopathy followed by fever, headache, myalgia, generalised lymphadenopathy,cough,gastrointestinal symptoms, rash, transient hearing loss and conjunctival injection [11].…”