Pelger-Huёt Anomaly in a Bitch Basenji

Abstract

Background: Pelger-Huët anomaly (PHA) is characterized by morphological changes in all granulocytes, being more evident in neutrophils. Granulocytic function in these animals remains unchanged. Hereditary form of PHA should be differentiated from pseudo-PHA,a condition acquired from infections and/or inflammation conditions. Recognition of PHA is important to avoid misleading leukogram interpretation, since hyposegmentation of neutrophils can be confused with left shift, making it necessary to carry out diagnostic tests and treatment for the disease that is generating the deviation. The objective of this case report was to demonstrate the importance of laboratory diagnosis in PHA.

Case: A 11-month-old bitch Basenji, was presented to perform preoperative evaluation for elective ovariosalpingohisterectomy at Veterinary Hospital (HUVET) of the Universidade Federal Fluminense (UFF). Tutor reported that animal was healthy, vaccination status was current, had deworming protocol applied and had not made use of medications recently. Animal presented normophagy, normodipsia, normuria and normochezia. Upon physical examination, animal was alert consciousness level, with adequate hydration, hyperemic oral mucosa, a less than 2 s capillary perfusion time, normal lymph nodes (submandibular, pre-scapular, inguinal and popliteal), rectal temperature of 39.2°C, heart rate of 160 beats per minute and respiratory rate of 60 movements per minute, possibly due to the animal’s agitated state. Abdominal palpation showed no changes. Physical examination presented no alterations. Preoperative exams included complete blood count (CBC) and biochemistry profile (ALT, AP, glucose, creatinine, urea, total proteins and fractions). Samples were sent to Hospital's Veterinary Clinical Pathology Laboratory (LABHUVET/UFF) for analysis. CBC was performed using automatic method. Blood smears were stained with hematological stain and then a cytomorphological evaluation was performed. The first CBC revealed 23% of neutrophils with nuclear hyposegmentation and 44% of neutrophils were bandsA follow up was performed after 9 months, and a Complete Blood Count was performed again in which 12% of neutrophils showed nuclear hyposegmentation with mature chromatin pattern, 40% of neutrophils were bands, 1% of meta-myelotcytes neutrophils, 1% of myelocytes neutrophils and, also, eosinophils with nuclear hyposegmentation. Animal was healthy, and had no alterations on physical examination suggesting a diagnosis of PHA.

Discussion: Recognition of PHA is important to avoid misleading leukogram interpretation, since neutrophils hyposegmentation can be confused with left shift, which is considered severe with poor prognosis, making it necessary to carry out diagnostic tests and treatment for the disease that is generating the deviation. The diagnosis of PHA was considered by the shape of the leukocytes nuclei, without evidence of inflammatory disease, during the patient follow up. Therefore, this anomaly should be considered as a differential diagnosis of left shift, thus avoiding unnecessary clinical and therapeutic procedures. Guidance in face of this hereditary hematological syndrome is important. The responsible guardian of the animal must not allow it to act as a breeder in order to interrupt possible transmission of this anomaly to offspring, because there is a fatal form when it comes to homozygotes.

Keywords: canine, dog, hereditary anomaly, WBC, nuclear hyposegmentation, neutrophils, left shift.