Presence of hypergonadotropic hypogonadism in dogs with primary adrenocortical insufficiency

Sammanfattning: Primary adrenocortical insufficiency (PAI) is a complex endocrine dysfunction that can occur in both dogs and humans. The three layers of the adrenal cortex are destroyed, which is most often an autoimmune process. There is evidence of other autoimmune endocrinopathies, such as hypothyroidism, occurring concurrently with PAI in dogs. This is also known in humans with PAI, as part of autoimmune polyendocrine syndromes that are genetically linked. Sometimes these syndromes can include dysfunction of the gonads, and a consequential hypergonadotropic hypogonadism (HH). The aim of this study was to investigate whether there is a connection between PAI and HH in dogs. Twenty intact Swedish dogs with PAI were selected from the patient records of the University of Agricultural Sciences animal hospital to be included in the study. Serum specimen were acquired and analysed for luteinizing hormone using a semi-quantitative rapid immunechromatographic essay. A positive test was interpreted as confirmed HH and a negative result as non-HH. A third category, suspected HH, was used for the cases when a clear test band was discernible of lower intensity than the control band. Animal hospital journals were utilized to acquire additional information about the dogs, such as for example whether they were diagnosed with other endocrinopathies. The female to male proportion of the dogs was 60% to 40% and the most common breed was Standard Poodle. The age of the dogs ranged from 2 to 10 years, with a median of 7 years. Phenotypically, the study group was comparable to what previously has been reported in studies on PAI. Out of the 20 dogs in this study, none had a clear positive result on the rapid essay. However, three dogs (15%), one female and two male dogs, were classified as having suspected HH. Interestingly two of these three dogs had concurrent hypothyroidism. The present study shows that HH may be present in dogs with PAI, and that suspected HH may occur in dogs with concurrent polyendocrine diseases. More studies are needed, including larger sample size and quantitative hormone analysis, before presence of HH can be confirmed in dogs with PAI.