Rickettesial Disease

• Suspect Rickettsial disease in any sick child with prolonged fever without any specific focus or obvious etiology.

• Check history of travel, look for eschar (a crusty necrotic lesion with or without surrounding erythematous halo) However presence of eschar is not necessary for diagnosis.

• Scrub typhus is endemic in India and may begin insidiously with headache, anorexia, and malaise, or start abruptly with chills and fever. As the illness evolves, most patients develop high fever, worsening of headache severity, and myalgias. An eschar or rash may develop in a subset of patients.

• Rash can involve palms and soles in Rocky mountain spotted fever whereas in the typhus group it usually spares palms and soles.

Laboratory Diagnosis

Serology by IFA is usually positive after 7 days and is gold standard for diagnosis. PCR can be done during the 1^st week. Both these are not easily available in India.

Serology by ELISA (2^nd week) and Weil Felix^# (2^nd week) still remains an important tool in the diagnosis in resource-limited settings.

Treatment: 

*Use of doxycycline for treatment of rickettsial diseases in children of any age is no longer a matter of controversy. Alternative effective drugs are macrolides (oral clarirthromycin or oral/intravenous azithromycin), chloramphenicol and rifampicin. Azithromycin is used in the dose of 10 mg/kg/ day.

^#Read about Weil Felix