Overview of Rickettsial Disease
Rickettsial disease is a collective term for a variety of acute infections caused by certain pathogenic microorganisms in the order Rickettsiae, with worldwide or endemic epidemics and varying severity of clinical manifestations.
Causes
The main vectors are arthropods such as ticks, lice, fleas, mites, etc. It can also occur due to scratching and biting by domestic animals such as cats and dogs.
Symptoms
Most rickettsial diseases may present clinically as a triad of fever, headache, and rash, most often in the spring and summer, often with a history of tick bites, recent camping, or occupational exposure.
Examination
1. Exophthalmos test
A titer of 1:160 or more is positive, and a 4-fold increase is more diagnostic. The test is simple, but the specificity is poor, and can be cross-agglutinated with return fever, malaria, typhoid fever, and Aspergillus infections, resulting in false positives.
2. Serologic diagnostic methods
IFA, enzyme-linked immunosorbent assay (ELISA), solid-phase radioimmunoassay (SPRIA) and indirect hemagglutination test can detect specific immunoglobulin M (IgM) or immunoglobulin G (IgG) with high specificity.
3. Others
Immunoelectron microscopy and polymerase chain reaction (PCR) are also useful for diagnosis.
Diagnosis
Methods used for the diagnosis of Rickettsial disease, but the better specificity and sensitivity are serologic diagnostic methods.
Treatment
1. Drug treatment
Doxycycline, tetracycline, chloramphenicol, etc. are quite effective in all kinds of rickettsial diseases.
2.Supportive therapy
For the diagnosis of critical patients, symptomatic supportive therapy is very important, severe patients with respiratory distress can be considered ventilator-assisted respiration, acute renal insufficiency can be considered dialysis treatment, and also pay attention to correct anemia and coagulation dysfunction.