Changes

==Aetiology==

==Aetiology==

Mhf is one of a group of organisms known as haemotropic mycoplasmas which infect several other domestic animal species. The causative organism was previously called Haemobartonella felis and thus the disease was known as haemobartonellosis. Polymerase chain reaction (PCR) assays allowing DNA analysis resulted in the reclassification of the organism in 2001¹. Two other haemotropic mycoplasmas (''Candidatus M. haemominutum'' and ''Candidatus M. turicensis'') have been identified in cats but appear to be less pathogenic².

Mhf is one of a group of organisms known as haemotropic mycoplasmas which infect several other domestic animal species. The causative organism was previously called Haemobartonella felis and thus the disease was known as haemobartonellosis. Polymerase chain reaction (PCR) assays allowing DNA analysis resulted in the reclassification of the organism in 2001¹. Two other haemotropic mycoplasmas (''Candidatus M. haemominutum'' and ''Candidatus M. turicensis'') have been identified in cats but appear to be less pathogenic².

Mhf can vary in shape from cocci to rods and are sometimes present in chains on the cell surface.

Mhf can vary in shape from cocci to rods and are sometimes present in chains on the cell surface.

The mode of transmission of Mhf is poorly understood. It is thought that it may be transmitted through biting and fighting activities, although this has not been able to be demonstrated experimentally. AS transmission has been shown to occur through blood transfusion, it is recommended that blood donors been screened³.

 

The mode of transmission of Mhf is poorly understood. It is thought that it may be transmitted through biting and fighting activities, although this has not been able to be demonstrated experimentally. As transmission has been shown to occur through blood transfusion, it is recommended that blood donors been screened³.

==Signalment==

==Signalment==

==Differential diagnosis==

==Differential diagnosis==

There are multiple causes of both regenerative and non-regenerative anaemia in cats which must be considered as differential diagnoses.  

There are multiple causes of both regenerative and non-regenerative anaemia in cats which must be considered as differential diagnoses when investigating anaemia in cats.  

 

 

 

For cats showing signs of regeneration causes of blood loss or haemolysis must be considered:

Major differential diagnoses for cats with non-regenerative anaemia include:

*Primary immune-mediated haemolytic anaemia

*neoplasia

*Heinz body haemolytic anaemia

*chronic inflammatory conditions

*Other infectious causes such as "Babesia felis" and "Cytauxzoon felis"

*underlying conditions such as diabetes mellitus and renal disease

The most commmon findings from complete blood counts from cats with Mhf infections are a marcocytic, hypochromic regenerative anaemia. Reticulocytes and Howell-Jolly bodies may be identified on cytologic examination.

The most commmon findings from complete blood counts from cats with Mhf infections are a marcocytic, hypochromic regenerative anaemia. Reticulocytes and Howell-Jolly bodies may be identified on cytologic examination.

Mhf infection can be definitvely diagnosed by identification of organisms on a blood smear, appearing as cocci or rods and sometimes forming short chains of organisms. However, examination of a single blood smear is less than 50% sensitive ⁵ as the animal's immune response causes organisms to disappear from the blood stream for several days, often to reappear a few days later. It was found in one study that smears should be examined every four days over a minimum of three four day cycles⁵. As there could be eight days between presentation and diagnosis this is clearly not an ideal means of diagnosis. It also has the potential for misidentification.  

Mhf infection can be definitvely diagnosed by identification of organisms on a blood smear, appearing as cocci or rods and sometimes forming short chains of organisms. However, examination of a single blood smear is less than 50% sensitive ⁵ as the animal's immune response causes organisms to disappear from the blood stream for several days, often to reappear a few days later. It was found in one study that smears should be examined every four days over a minimum of three four day cycles⁵. As there could be eight days between presentation and diagnosis this is clearly not an ideal means of diagnosis. It also has the potential for misidentification.  

==Treatment==

==Treatment==