La enfermedad de Addison (EA), la hiperplasia adrenal congénita (HAC) por déficit de 21 αhidroxilasa adrenal y el hipoparatiroidismo (HoPTH) son de diagnóstico poco frecuente, representando el 3% (EA) y 0,5% (tanto HAC como HoPTH) de las enfermedades endócrinas atendidas. Se describen 1 caso de EA congénito (collie de 6 meses de edad), 2 casos de HAC (una caniche toy y una labradora, ambas de 2 años) y 2 de HoPTH (cocker spaniel de 11 meses y una mestiza de 7 años). Por la signología clínica que presentaban (enanismo; obesidad con alopecia bilateral simétrica en periné, hiperpigmentación, anestro y convulsiones) los diagnósticos presuntivos, para cada caso, fueron de hipotiroidismo, déficit de hormona de crecimiento o panhipopituitarismo (EA); hipotiroidismo o Síndrome de Cushing (HAC) y síndrome convulsivo (HoPTH). Para el diagnóstico definitivo de cada enfermedad se indicó estudio de los ejes somatotropo (por medio del factor insulina símil-1); adrenal (adenocorticotrofina endógena [ACTHe] y Estimulación con ACTH, midiendo cortisol y 17 hidroxiprogesterona [17 OH-P]) y tiroideo. Se midió la paratohormona (PTH), Vitamina D y calcio iónico [Ca^+]. El cachorro con EA, la ACTHe estaba elevada y la estimulación con ACTH (cortisol) hiporrespondiente, estando normales las restantes hormonas. Las perras con HAC la ACTHe fue elevada, con hiporrespuesta del cortisol e hiperrespuesta de la 17 OH-P a la estimulación con ACTH, siendo ambas eutiroideas. La PTH y [Ca^+] estaban descendidas en los casos de HoPTH, habiendo asociación con Síndrome de Cushing en la mestiza. Se concluye que debe incluirse la EA, HAC e HoPTH como diagnósticos presuntivos.175 - 181vcastill@fvet.uba.arBimestralAddison is disease (AD), congenital adrenal hyperplasia (CAH) produced by 21-alpha hydroxylase deficiency and hypoparathyroidism (HoPTH) are uncommon endocrinopathologies. The frequency of presentation was 3% and 0.5% (both CAH and HoPTH) of total endocrine diseases diagnosed. One case with AD (collie, male, 6 months old), two cases with CAH (2 females, poodle and labrador retriever, both of 2 years of age), and two cases with HoPTH (an eleven (11) month old cocker spaniel male, and a seven (7) yaer old mongrel female) are reported. According to the pathology, the dogs presented several clinical signs as such as dwarfism, obesity with hair loss, hyperpigmentation, anestro, and convulsive syndrome. The presumptive diagnoses for each case were hypothyroidism, growth hormone deficiency or panhypopituitarism (AD); hypothyroidism or Cushing’s Syndrome (CAH) and convulsive syndrome (HoPTH). In order to make a definitive diagnosis of each disease a study of somatotrope axes (using the insulin factor-1), adrenal (endogenous Adrenocorticotropic hormone [eACTH], ACTH stimulation test, cortisol measurement, and 17 hydroxyprogesterone [17 OH-P]) and thyroid. Parathyroid hormone (PTH), Vitamin D and ionized calcium were also measured. In the puppy with AD, only the eACTH was increased (the other hormones were withinin normal range) and the ACTH stimulation test was hyper-responsive. For the females with CAH, eACTH was elevated, the cortisol and 17 OH-P presented hyper-responses to ACTH stimulation. Thyroid hormones were normal in both of them. In the dogs with HoPTH, PTH concentration and ionized calcium were low. In the mongrel female it was associated with Cushing’s Syndrome. The conclusion is that AD, CAH and HoPTH should be included in presumptive diagnosis.