ABNORMAL FINDINGS IN HAEMOGRAMS OF DACHSHUND PUPPIES: PRESUMPTIVE (IMMUNODEFICIENCY) FAMILIAL DISEASE

In a litter of seven Dachshund puppies, one subject was stillborn and six presented with diffuse skin infections characterized by dermatitis, abscessatio n, pustules, crusts and ulcers. Two of the puppies w re referred for further evaluation. One male puppy was referred at four months of age and a sister litter mate was referred two months later. A complete blood count, biochemical and histological examination were perfo rmed on these puppies to identify the pathologic process . Clinical, biochemical, haematological and histolo gical evaluation of subjects. This report characterizes q uantitative and qualitative haematological abnormal ities in two puppies that resulted in a diagnosis of dysmyel opoiesis. The existence of a familial immunodeficie n y syndrome was speculated. This is the first report o f such a syndrome in Dachshund puppies.


Case Presentation
In a litter of seven Dachshund puppies, one was stillborn and six presented with diffuse skin infection characterized by dermatitis, abscessation, pustules, crusts and ulcers. Two of the puppies were referred for further evaluation.
Microscopic evaluation of the blood smear revealed the presence of keratocytes, schistocytes, anulocytes and severe signs of dysplasia in both neutrophils and monocytes. The dysp lasia was characterized by abnormal nuclear shape, hypersegmented and/or hyposegmented nuclei, irregular chromatin pattern and atypical cytoplasmic granules. The platelets were dysplastic to an extent that they were initially mistaken for blood parasites, because most of them had a tail-like structure ( Fig. 1 and 2). Clinical signs of altered primary hemostasis were not evident. For this reason, PCR screening for Trypanosoma spp. was performed, but it was negative. Cytological diagnosis of dysmyelopoiesis was made.

AJAVS
with increase in acute phase protein fractions was attributed to the persistent infection.
The dog died three days after referral and before bone marrow sampling could be attempted. Necropsy and histopathological examinations were carried out and the results showed: multifocal, necrotizing to suppurative hepatitis, neutrophilic lymphadenitis of the mesenteric lymph nodes, ulcerative enteritis of the small intestine and extramedullary hematopoiesis in the spleen. The histological findings were suggestive of septicemia.
As the dog's clinical condition continued to worsen, she was euthanized at 8 month of age.
Unfortunately, permission for cytological examination of the bone marrow could not be obtained. This prevented the definitive diagnosis of a dysmyelopoiesis.
Further information on the other litter mates was supplied by the referring practitioner.

Case 3-4
Another puppy from the same litter presented with similar skin lesions and died four months after birth. A diagnosis of peritonitis and suppurative mesenteric lymphadenitis was made following necropsy. Another puppy also presented with similar skin lesions in addition to a severe diarrhea. She was euthanized at five-months of age and numerous abscesses were found in the liver and mesenteric lymph nodes during necropsy.

Case 5-6
These subjects presented with similar clinical symptoms but died before they could be referred to the hospital.

DISCUSSION
Dysmyelopoiesis is defined as a hematologic disorder characterized by the presence of morphologic abnormalities (i.e., dysplasia) in one or more hematologic cell lines in the blood or bone marrow (Weiss, 2006;Weiss and Wardrop, 2011). Dysmyelopoieses are divided into myelodysplastic syndromes, secondary dysmyelopoiesis and congenital dysmyelopoiesis. Causes of dysmyelopoiesis include acquired mutations in hematopoietic stem cells (i.e., myelodysplastic syndromes), congenital defects in hematopoiesis and dysmyelopoietic conditions associated with various disease processes, drug treatments, or toxin exposure (Weiss, 2005). The congenital forms, causing functional defects, have been well described in some canine breeds: e.g., Canine Leucocytes Adhesion Deficiency (CLAD) in Irish Setter and Irish setter-cross-bred, chronic granulomatous disease in Dobermann Pinschers, myeloperoxidase deficiency in Gray Collies, altered chemiluminescence in Weimaraners and Pelger-Huet anomaly (Weiss and Wardrop, 2011).
CLAD was initially described in a male Irish setter by Renshaw et al. (1975) and collegues, they called the condition "Canine granulocitopathy syndrome". The dogs had a clinical history of recurrent infections associated with pyrexia and neutrophilia and circulating leukocytes isolated from the dog at 5 months of age showed a bactericidal defect due to abnormal expression of the CD11b/CD18 complex . The puppies described in this report showed severe skin lesions and septicemia, both phenomenons can be attributed to a neutrophil hypofunction. Neutrophils are essential to preventing bacterial infection and dogs with naturally occurring septic and non-septic inflammatory diseases had an increased cell-expression of CD11b (Weiss and Wardrop, 2011). Hence, we might speculate that they were affected by a Canine granulocitopathy syndrome.
A single case of cabot ring cells has been reported in the Dachshund. This was characterized as a severe dyserythropoiesis in an 11-year-old female that presented with depression, diarrhea, weight loss and radiographic evidence of abdominal masses (Lukaszewska and Lewandowski, 2008). Examination of the peripheral blood smear revealed erythroid dysplasia, anisocytosis with macrocytosis, Howell Jolly bodies, atypical nucleated cells, neutrophil hypersegmentation and the presence of giant forms. The final diagnosis was myelodysplasia secondary to metastatic adenocarcinoma (Lukaszewska and Lewandowski, 2008).
A review on Pneumocystis carinii in the miniature Dachshund reported four cases with hyperpnoea, tachypnoea, exercise intolerance and signs suggestive of immune incompetence. It is probable that Pneumocystis carinii infection in these cases was the result of an immunodeficiency (Lobetti et al., 1996).
The hematological findings of both leukocytosis and severe leukocytic dysplasia is suggestive of an abnormal function of the bactericidal cells. Tests on neutrophil function were not performed in these cases because it was not possible to access the appropriate diagnostic tests in Italy. However, both the morphological cellular abnormalities and the clinical symptoms are suggestive of reduced cell function and consequently, a functional defect of the immune system. The death of other four puppies supports the hypothesis of a familial immunodeficiency.

CONCLUSION
This is the first report describing a familial imunodeficiency syndrome in Dacschund dogs characterized by significant hematological changes, particularly of the leukocyte cells

ACKNOWLEDGEMENT
Researchers acknowledged to Dr E. Owen (University of Queensland, Australia) the both the scientific and English editing of the manuscript.