The Pathophysiology of Diabetes Mellitus in Dogs and Cats

Među metaboličkim bolestima koje se javljaju u psa i mačaka, veliku važnost ima diabetes mellitus. Kada govorimo o dijabetesu, govorimo o kompleksnom kroničnom poremećaju koji sve češće zahvaća kućne ljubimce. Karakteristike šećerne bolesti su kronična hiperglikemija, poremećaj pretvorbe ugljikohidrata, masti i bjelančevina i poremećaj u lučenju ili djelovanju inzulina. Etiologija bolesti je kompleksna i multifaktorijalna, postoji više čimbenika koji uvjetuju nastanku bolesti, te etiologija nije u potpunosti jasna. Klasifikacija dijabetesa u psa i mačaka sa patofiziološkog stajališta bazira se na dva osnovna oblika. U psa je značajno češći diabetes mellitus tip 1, koji nastaje zbog oštećenja beta stanica gušterače ili zbog bolesti koje ometaju proizvodnju inzulina, pri čemu dolazi do potpunog manjka inzulina. U mačaka značajno češći je diabetes mellitus tip 2, gdje dolazi do smanjenja osjetljivosti ciljnih tkiva na učinak inzulina,tj. do inzulinske rezistencije, a čimbenici koji pogoduju nastanku su pretilost, fizička neaktivnost, ostale endokrinopatije te dugotrajna terapija dijabetogenim lijekovima. Klinički znakovi bolesti uključuju poliuriju, polidipsiju, polifagiju i mršavljenje. Znakovi bolesti često su nejasni vlasnicima ili ih vlasnik zanemari, pa dolazi do komplikacija bolesti koje mogu rezultirati smrću pacijenta. Diabetes mellitus se dijagnosticira kada su istovremeno prisutni tipični klinički znakovi, stalna hiperglikemija i glukozurija. Pošto govorimo o kroničnom metaboličkom poremećaju, vlasnici moraju biti spremni da je njihovim ljubimcima potrebna terapija cijeli život. Terapija se bazira na egzogenom unosu inzulina, dijetalnom režimu prehrane, vježbanju u psa i oralnim hipoglikemijskim lijekovima kod dijabetesa tipa 2. Jedan od najvažnijih aspekta uspješnosti terapije je odnos vlasnika i veterinara, pri čemu vlasnici moraju biti odgovorni, voljni slijediti predloženu terapiju i omogućiti monitoring pacijenta da bi se procijenila uspješnost provedene terapije.Among the metabolic diseases that occur in dogs and cats, diabetes mellitus carries great importance. A complex chronic disorder, it is affecting an increasing number of pets. Diabetes is characterized by chronic hyperglycemia,a disorder in the arbohydrates, fats and proteins metabolism, as a conseqence of disorder in the secretion or effects of insulin. The etiology of the disease is complex and multifactorial; several factors determine the occurrence of the disease, which in itself is not entirely understood. Diabetes in dogs and cats, from a pathophysiological perspective, is classified into two basic forms. Dogs are the most common victims of type 1 diabetes, which occurs due to damage of the pancreatic beta cells, or due to disturbances in insulin production, either way, causing a complete insulin deficiency. Cats more often suffer from type 2 diabetes, where target tissues experience a decreased sensitivity to the effects of insulin, i.e. insulin resistance, while factors that will play into development of this condition are: obesity, physical inactivity, endocrinopathies, and long-term therapy with diabetogenic drugs. Clinical signs of the disease include polyuria, polydipsia, polyphagia, and weight loss. Symptoms are frequently vague and therefore go unnoticed by owners until a potentially life-threatening complication arises. Diagnosis is confirmed when appropriate clinical signs are presented together with persistent hyperglycaemia and glucosuria. Because of the chronicity of the disease, owners need to be prepared for the fact that their pets will need treatment for the entirety of their lives. Treatment is based on administering exogenous insulin, maintaining a strict diet regime, exercising, and, in type 2 diabetes, administering oral hypoglycaemic agents. One of the key aspects of successful treatment is a healthy relationship between owners and veterinarians, wherein owners must be responsible and willing to follow the proposed therapy, and enable monitoring of the patient to assess the success of the therapy