Fibrous osteodystrophy due to secondary renal hyperparathyroidism in a senile dog / Osteodistrofia fibrosa decorrente de hiperparatireodismo secundário renal em cão senil

Renal hyperparathyroidism stands out among the complications of kidney disease in dogs due to phosphorus retention with a predisposition to hypocalcemia, parathyroid hormone stimulation with mobilization of calcium from the bones, characterizing fibrous osteodystrophy, unusual in the elderly. The objective was to report it in 12-year-old Labrador with polyuria, polydipsia, and emesis for five months due to maxillary and mandibular volume increase, followed by loosely fixed teeth, and facial deformity. Blood tests showed anemia, thrombocytosis, azotemia, hypoalbuminemia and hyperphosphatemia and urinalysis showed low density, glycosuria, proteinuria, and moderate caudate and transitional epithelial cells. Oral x-rays showed loss of dental bone support and decreased bone radiopacity. Chest radiographs showed decreased density in the ribs and costochondral junction; on the other hand, organs of the cardiorespiratory system showed no changes. The electrocardiogram and echocardiogram did not show impairment. Abdominal ultrasound revealed kidneys with asymmetry, increased echogenicity of the cortical and poorly preserved cortico-medullary definition. Oral histopathology showed intense fibroplasia associated with bone reabsorption. Support therapy was instituted, but the patient died ten days after consultation. Thus, although uncommon in the elderly, fibrous osteodystrophy should be investigated in dogs with advanced-stage chronic kidney disease and, even with conservative therapies, the prognosis is unfavorable.

O hiperparatireoidismo renal destaca-se entre as complicações da doença renal em cães, pela retenção de fósforo com predisposição à hipocalcemia, estimulação de paratormônio com mobilização do cálcio dos ossos, caracterizando a osteodistrofia fibrosa, incomum em idosos. O objetivo foi relatá-la em Labrador de 12 anos com poliúria, polidipsia e vômitos há cinco meses, além de aumento de volume maxilar e mandibular seguido de dentes frouxamente fixados e deformidade facial. Os exames sanguíneos denotaram anemia, trombocitose, azotemia, hipoalbuminemia, hiperfosfatemia, urinálise, baixa densidade, glicosúria, proteinúria e moderadas células caudadas e epiteliais de transição. Pelos raios X orais, houve perda da sustentação óssea dentária e diminuição da radiopacidade óssea. As radiografias de tórax demonstraram diminuição da densidade óssea na região dos arcos costais e junção costocondral; em contrapartida, órgãos do sistema cardiorrespiratório se mostraram sem alterações aparentes. O eletrocardiograma e o ecocardiograma não incidiram comprometimento. O ultrassom abdominal revelou rins com assimetria, aumento da ecogenicidade cortical e definição corticomedular pouco preservada, e a histopatologia oral apontou intensa fibroplasia associada à reabsorção óssea. Foi instituída terapia suporte, mas o paciente veio a óbito 10 dias após a consulta. Assim, mesmo que incomum em idosos, a osteodistrofia fibrosa deve ser investigada em cães com doença renal crônica em estágio avançado, mesmo com as terapias conservadoras, o prognóstico é desfavorável.

Maxillomandibular deformity in a canine with fibrous osteodystrophy secondary to chronic kidney disease

Background: Cases of renal fibrous osteodystrophy are usually associated with nutritional causes, which of renal causesare considered uncommon in dogs. This disorder is characterized by the intense proliferation of fibrous connective tissue inbones, impairing bone stiffness. The aim of this study was to report a case of fibrous osteodystrophy secondary to chronickidney disease in a canine with a “rubber jaw” facial deformity.Case: A 4-year-old male unneutered mongrel dog weighing 5.2 kg had a history of apathy, progressive weight loss andvomiting for one month, and polyuria and polydipsia for more than three months. In addition, the owner complained aboutthe deformed appearance in the muzzle region of the animal, which was evidenced flexibility of the same, with a displacement of the mandible and maxilla on physical examination, similar to the “rubber jaw”. Blood tests revealed macrocyticanemia, elevated total plasma proteins, and lymphopenia-associated neutrophilia, as well as hyperphosphatemia (24 mg/dL), uremia (283.6 mg/dL) and increased creatinine (8.6 mg/dL), ALT (143.2 UI/L) and alkaline phosphatase (3222.2UI/L), while calcium (8.8 mg/dL) and albumin (1.9 g/dL) were decreased. A serological test for visceral leishmaniasis wasalso performed, which was negative. Abdominal ultrasound imaging revealed kidneys with alterations in tissue architecture, increased thickness and complete loss of cortico-medullary relationship, while the parathyroid gland was enlargedand spindle-shaped. Cranial radiography showed marked radiopacity of the bilateral maxillary bones, with destructionof the nasal, turbinate and frontal bones, as well as loosening of the teeth and destruction of the mandibular bone matrix,characterizing an aspect of “rubber jaw”. Based on the history, history and evidence of azotemia, hyperphosphatemia andloss of facial bone density, the diagnosis of fibrous osteodystrophy secondary to chronic kidney...

Maxillomandibular deformity in a canine with fibrous osteodystrophy secondary to chronic kidney disease

Background: Cases of renal fibrous osteodystrophy are usually associated with nutritional causes, which of renal causesare considered uncommon in dogs. This disorder is characterized by the intense proliferation of fibrous connective tissue inbones, impairing bone stiffness. The aim of this study was to report a case of fibrous osteodystrophy secondary to chronickidney disease in a canine with a “rubber jaw” facial deformity.Case: A 4-year-old male unneutered mongrel dog weighing 5.2 kg had a history of apathy, progressive weight loss andvomiting for one month, and polyuria and polydipsia for more than three months. In addition, the owner complained aboutthe deformed appearance in the muzzle region of the animal, which was evidenced flexibility of the same, with a displacement of the mandible and maxilla on physical examination, similar to the “rubber jaw”. Blood tests revealed macrocyticanemia, elevated total plasma proteins, and lymphopenia-associated neutrophilia, as well as hyperphosphatemia (24 mg/dL), uremia (283.6 mg/dL) and increased creatinine (8.6 mg/dL), ALT (143.2 UI/L) and alkaline phosphatase (3222.2UI/L), while calcium (8.8 mg/dL) and albumin (1.9 g/dL) were decreased. A serological test for visceral leishmaniasis wasalso performed, which was negative. Abdominal ultrasound imaging revealed kidneys with alterations in tissue architecture, increased thickness and complete loss of cortico-medullary relationship, while the parathyroid gland was enlargedand spindle-shaped. Cranial radiography showed marked radiopacity of the bilateral maxillary bones, with destructionof the nasal, turbinate and frontal bones, as well as loosening of the teeth and destruction of the mandibular bone matrix,characterizing an aspect of “rubber jaw”. Based on the history, history and evidence of azotemia, hyperphosphatemia andloss of facial bone density, the diagnosis of fibrous osteodystrophy secondary to chronic kidney...(AU)

Fibrous Osteodystrophy in a Captive Common Eland Antelope (Taurotragus oryx)

Fibrous osteodystrophy (FO) is a common condition described mainly in domestic species, with only few cases described in wild ones kept in captivity. Herein we report a case of FO in a 2 yr-old female common eland antelope (Taurotragus oryx) maintained in captivity and fed with a horse pelleted ration plus hays. The animal showed a firm bilateral symmetrical enlargement of upper maxillary bones which was submitted to histological evaluation. Microscopic findings were those related to extensive bone resorption and fibroplasia.(AU)

Osteodistrofia fibrosa nutricional em caprinos / Nutritional fibrous osteodystrophy in goats

Seven out of 25 goats from a southern Brazilian flock developed nutritional fibrous osteodystrophy. Affected animals were younger than 1 year of age and were confined in stalls and fed a concentrate ration containing 1:6 calcium:phosphorus ratio. The remaining flock (35 goats) was managed at pasture and showed no disease. Clinical signs were characterized by mandibular and maxillary enlargements, varying degrees of mouth opening and protruding tongue, dyspnea, apart of abnormalities of prehension and mastication. Affected animals had increased seric levels of phosphorus and parathormone, as well as higher alkaline phosphatase activity. Postmortem examination on three succumbed goats revealed bilateral enlargement of the maxilla and mandibula, and loose teeth, apart of multiple incomplete rib fractures in one of them. Severe diffuse proliferation of loose connective tissue surrounded the osteoid trabeculae, many of which were partially or completely non-mineralized. Mineralized osteoid trabeculae showed osteoclasts in the Howship's lacunae.(AU)

Sete de um total de 25 caprinos jovens (menos de um ano de idade) de um rebanho no sul do Brasil desenvolveram osteodistrofia fibrosa nutricional. Os animais afetados eram confinados em baias e alimentados com concentrado, cuja relação Ca:P era 1:6. O restante do rebanho (35 cabras) era mantido na pastagem e não desenvolveu a doença. Os sinais clínicos se caracterizaram por aumento de volume da mandibula e maxila, vários graus de abertura de boca com protrusão da língua, em associação com dispneia e anormalidades de apreensão de alimento e mastigação. Os animais afetados apresentaram os níveis séricos de fósforo e paratormônio aumentados, bem como maior atividade de fosfatase alcalina. Três caprinos foram necropsiados e os achados de necropsia incluíram aumento bilateral da maxi-la e mandíbula, dentes frouxos, além de múltiplas fraturas incompletas de costelas em um caprino. Microscopicamente, havia intensa proliferação de tecido conjuntivo frouxo ao redor de trabéculas ósseas, muitas das quais estavam parcial ou completamente não mineralizadas. Trabéculas ósseas mineralizadas apresentaram osteoclastos em lacunas de Howship.(AU)

Osteodistrofia fibrosa em equinos criados em pastagem de Panicum maximum cultivar Aruana: relato de casos / Fibrous osteodystrophy in horses raised on Aruana (Panicum maximum) pasture: case reports

Relata-se a ocorrência de osteodistrofia fibrosa em 38 equinos criados em pastagens de Panicum maximum cultivar Aruana, da raça Mangalarga Marchador, provenientes de uma propriedade localizada no estado do Paraná. No exame clínico geral, observou-se aumento bilateral e simétrico dos ossos da face e, também, aumento de volume na porção distal do rádio. A análise radiológica das áreas afetadas demonstrou redução da densidade óssea, e, na bioquímica sanguínea, 24 (63 por cento) animais apresentaram níveis de fósforo elevados. O exame bromatológico revelou níveis elevados de oxalato na pastagem de Aruana. Conclui-se que a ingestão de Aruana, forragem com altos níveis de oxalato, foi responsável pelo aparecimento de lesões de osteodistrofia fibrosa em equinos.(AU)

Fibrous osteodystrophy occurrence is reported in 38 Mangalarga Marchador horses raised on Aruana (Panicum maximum) pasture from a breeding farm in Paraná state. Clinical examination showed bilateral and symmetric increase in bones of face and an increase of volume at the radius distal portion. The radiologic analysis revealed bone density reduction in affected areas. Blood biochemist demonstrated high phosphorus levels in 24 animals (63 percent). Analysis of the pasture was performed and high levels of oxalate were found in the Aruana samples. It was concluded that the ingestion of Aruana, a pasture with high oxalate levels, was responsible for the appearing of fibrous osteodystrophy lesions in horses.(AU)

Renal dysplasia in a Boxer dog: case report / Displasia renal em um cão Boxer: relato de caso

A 20-month-old female Boxer dog presented significant increase on the bilateral volume of the maxillaries. The necropsy revealed that the kidneys were reduced in size, pale, with lobular aspect, and reduced cortical-medullar ratio. The maxillaries cutting surface revealed trabecular aspect of brown-reddish color. In addition, the lesions observed by microscopy (asynchronic differentiation of nephrons, persistent mesenchyme, and atypical tubular epithelium) allowed establishing the diagnosis of renal dysplasia with secondary fibrous osteodystrophy.(AU)

Uma cadela Boxer com 20 meses de idade apresentou grande aumento de volume bilateral nos maxilares. À necropsia, os rins apresentavam-se diminuídos de tamanho, pálidos, com aspecto lobular e relação córtico-medular reduzida. A superfície de corte dos maxilares revelou aspecto trabecular de coloração marrom-avermelhada. As lesões observadas à microscopia (diferenciação assincrônica de néfrons, mesênquima persistente e proliferação tubular atípica) permitiram estabelecer o diagnóstico de displasia renal com osteodistrofia fibrosa secundária.(AU)

Fibrous osteodystrophy in a captive common eland antelope (Taurotragus oryx)

Fibrous osteodystrophy (FO) is a common condition described mainly in domestic species, with only few cases described in wild ones kept in captivity. Herein we report a case of FO in a 2 yr-old female common eland antelope (Taurotragus oryx) maintained in captivity and fed with a horse pelleted ration plus hays. The animal showed a firm bilateral symmetrical enlargement of upper maxillary bones which was submitted to histological evaluation. Microscopic findings were those related to extensive bone resorption and fibroplasia