Clinical Communication: A Case of Hyperostosis due to Hypervitaminosis A in a Cat

Abstract— —A case of hyperostosis in a cat is reported. Evidence indicated that the condition was caused by excessive vitamin A intake, in a predominantly liver diet, over a period of 18 months. The diagnosis, made on the case history and physical findings at examination was confirmed by radiological findings and clinical chemistry. It was further substantiated by autopsy findings. To re-affirm the clinical findings, photographs of macerated hyperostotic bones are presented. The case is discussed and its features are compared with feline oesteodystrophia fibrosa (osteogenesis irnperfecta, juvenile osteoporosis). Résumé— —On rapporte un cas d'hyperostose chez le chat. Les faits montrent que la maladie est provoqute par une absorption excessive de vitamine A au cours d'un régime dans lequel prédomine le foie pendant une période de 18 mois. Le diagnostic établi d'après les commémoratifs et les observations cliniques est confirmé par les observations radiologiques et les analyses biochimiques. Il est aussi renforcé par la suite au cours de l'examen nécropsique. Pour illustrer les constatations cliniques des photographies d'os hypero-stotiques sont présentées. Le cas est discuté et les faits sont comparés avec l'ostéodystrophie fibreuse du chat (ostéogénèse imparfaite, ostéoporose juvénile). Zusammenfassung— —Es wird über einen Fall von Hyperostose bei einer Katze berichtet. Der Befund liess darauf schliessen, dass der Zustand durch übermässige Vitamin-A-Aufnahme mit einem übenviegend aus Leber bestehenden Futter während eines Zeitraums von 18 Monaten verursacht worden war. Die Diagnose auf Grund der Krankengeschichte und der körperlichen. Untersuchungsergebnisse wurde durch radiologische und klinisch-chemische Untersuchung bestätigt. Weiter wurde sie durch den Sektionsbefund verifiziert. Als Belege werden die klinischen Befunde und Photographien der mazerierten hyperostotischen Knochen wiedergegeben. Der Fall wird besprochen und seine Besonderheiten werden mit Osteodystrophia fibrosa der Katze (Osteo-genesis imperfecta, juvenile Osteoporose) verglichen.     

Effect of topical 0.02% tacrolimus aqueous suspension on tear production in dogs with keratoconjunctivitis sicca

Objective To investigate the effect of 0.02% tacrolimus in aqueous suspension on tear production in dogs with keratoconjunctivitis sicca (KCS). Animals studied One hundred five dogs diagnosed with KCS [Schirmer tear test (STT) ≤ 10 mm/min and clinical signs of dry eye]. Eyes with marginally decreased STT (11 ≤ 15 mm/min) and clinical signs of dry eye were also evaluated. Procedure The investigation was conducted in two parts: an initial efficacy study and a subsequent double blinded controlled study. In the efficacy study, the effect of topical tacrolimus (formerly FK‐506) on tear production in dogs with primary KCS was evaluated. Dogs were divided into four categories: 1) 59 eyes (38 dogs) naïve to tear stimulation therapy with initial STT ≤ 10 mm/min; 2) 28 eyes (21 dogs) naïve to tear stimulation therapy with initial STT 11 ≤ 15 mm/min; 3) 30 eyes (15 dogs) maintained successfully on CsA therapy; 4) 47 eyes (24 dogs) unresponsive to CsA therapy. STT and clinical signs were evaluated prior to and after 6 to 8 weeks of twice daily tacrolimus administration. Tacrolimus was substituted for CsA therapy in categories 3 and 4. The controlled study compared the effect of topical tacrolimus in aqueous suspension to administration of the aqueous carrier alone on tear production in 20 dogs with primary KCS. Results In the efficacy study, STT increased by 5 mm/min in 84.7%, 25.0%, 26.7% and 51.1% of eyes in categories 1, 2, 3 and 4 respectively after tacrolimus administration. Eighty‐three percent of eyes with extremely low initial STT (≤ 2 mm/min), increased 5 mm/min after tacrolimus. In the controlled study, STT increased by 5 mm/min in 7/10 dogs (14/20 eyes) that received tacrolimus and in none of the 10 dogs that received aqueous carrier alone. Dogs receiving just the aqueous carrier were subsequently treated with tacrolimus, and STT increased 5 mm/min in 9 dogs (18/20 eyes) after administration. Conclusions Twice daily administration of 0.02% tacrolimus in aqueous suspension effectively increased tear production in dogs with KCS. Topical tacrolimus is a promising alternative to topical CsA for treatment of KCS and may be beneficial in patients with less than optimal response to topical CsA.