Rickettsia rickettsii - Lab diagnosis, Clinical Manifestation/Syndrome

Laboratory Diagnosis of Rickettsia rickettsii

The laboratory diagnosis of Rickettsia rickettsii begins with the collection of samples.

Specimen

• Skin biopsy

• serum

Culture

The culture of Rickettsia rickettsii can be done by following methods:

1. Egg culture

2. animal culture

3. tissue culture

Direct antigen (Ag) detection

Specific anti-rickettsial antibody labeled with the fluorescent compound in direct Antigen detection used for detection of Rickettsia rickettsii in skin biopsy.

Serodiagnosis

The serodiagnosis Rickettsia rickettsii can be done by following methods:

• Indirect Immunofluorescence Assay – detect IgG and IgM

• ELISA

DOT assay

Weil-Felix test

Clinical manifestation/syndrome

Rickettsia rickettsii is the causative agent of the Rocky Mountain spotted fever.

The incubation period of 7 days and symptoms includes fever, severe headache, chills, and myalgia. After 2-4 days of onset of fever, a spotted rash appears on wrists, forearms, ankles, palms, and soles.

Other clinical manifestations/syndromes include low platelet count, low sodium level in the blood, and elevated liver enzymes are severe in immunocompromised patients.