Human granulocytic anaplasmosis
The Humane granulocytic anaplasmosis ( HGA ) is caused by Anaplasma phagocytophilum infectious bacterial disease of human beings. It was formerly known as Human granulocytic ehrlichiosis ( HGE ) refers.
The first description of the disease took place in the 1990s.
Transmission
Transmission to humans by tick bites. The most common carriers in Europe is the tick (Ixodes ricinus), Ixodes scapularis in North America, especially Ixodes pacificus and. A protection against ticks is thus at the same time infection prevention.
Epidemiology
Ticks infected with Anaplasma phagocytophilum, and patient sera contain antibodies to this bacterium have been found in many European countries ( among others in Belgium, Germany, England, France, Great Britain, Italy, the Netherlands, Norway, Sweden, Austria, Switzerland and Slovenia).
In southern Germany, 1.6 to 4 % of adult Ixodes ricinus ticks are infected. The prevalence of antibodies, confirming a previous contact with the pathogen, is located in Germany at 1.9 and 2.6%. In high-risk groups, such as forest workers and forest rangers, it is considerably higher at 11.4 to 18.4 %.
Nevertheless, so far in Germany so far produced any solid case of acute granulocytic anaplasmosis disease to human known. Case reports from the USA, Austria, Slovenia, Portugal, Belgium and Italy are against it.
Since Anaplasma phagocytophilum dogs (→ Canine anaplasmosis ), ruminants, cats and horses attacks, these represent a reservoir of pathogens
Clinic
As feared serious complications are multi-organ failure, meningoencephalitis and acute respiratory distress syndrome, which occur mainly in immunocompromised patients (HIV, organ transplantation). The mortality rate of symptomatic anaplasmosis is 2 to 3%.
Diagnostics
Even without clinical symptoms typical laboratory changes can be found in 86% of all infected persons. In addition to an increase in liver transaminases also includes a leucopenia with lymphopenia and neutropenia, and thrombocytopenia. C-reactive protein (CRP) and erythrocyte sedimentation rate is increased. The creatine kinase may be increased.
With a suspicion of anaplasmosis of microscopic direct detection of morulae in blood smears, the detection of specific DNA by PCR, the cultivation in cell culture and the detection of antibodies on immunofluorescence test can be performed. Later Titeruntersuchungen can not be used as a control, because antibodies long after elimination of the pathogen may persist. PCR testing is slightly more reliable but it does not provide perfect security.
Therapy
Treatment of choice is doxycycline. In humans, each 100 mg per day for two to three weeks are recommended twice daily. In a contraindication of doxycycline a gift of rifampicin is possible.