Haemotropic Mycoplasmas (Haemoplasmas): A Review

Haemoplasmas contain Eperythrozoon and Haemobartonella species, which are widespread causes of animal and human infections. These obligatory cell parasites were previously known as Hemobartonella; now hemotropic mycoplasmas. These bacteria are identified by the lack of cell wall and their small genome. The usual diameter is between 0.3 and1μm. Mycoplasmasarepolymorphic and seen in circular or bar shape, which aggregate and form pinion teeth on the surface of RBCs. Despite the small genome of mycoplasmas, the GC content is 23 to 40%.The genome contains a circular double stranded DNA. Mycoplasmas are notable to grow on culture media. Animals are usually infected with the hidden form of the disease and hence become carriers and sources for the spread of the infection. Since these bacteria are difficult to grow, the common methods of diagnosis are cytology and microscopic examinations. Today, the most reliable and definitive method for the detection of haemoplasmas polymerase chain reaction (PCR).The most important way for the transmission of bacteria is the insect bite including ticks. High density of hemotropic mycoplasmas causes RBC hemolysis and hence many symptoms including jaundice, lethargy, anemia, fever and acidosis. Mycoplasmas respond to antibiotic therapy. Effective antibiotics are available such as lincomycin, enrofloxacin, oxytetracycline and doxycycline. Hemoplasmas cause a wide range of diseases and play the role of a cofactor in many viral and neoplastic diseases. These diseases are common in many countries, including Iran.