Occult UTI and discordinate Fructosamine in a Diabetic from Indonesia

OCCULT UTI AND DISCORDANT FRUCTOSAMINE IN A DOG WITH PANCREATITIS-

ASSOCIATED DIABETES MELLITUS: A CASE REPORT USING CGM

Maulana Ar Raniri Putra

Modernvet Animal Hospital, Jakarta, Indonesia

Abstract: An 11-year-old castrated male Yorkshire Terrier presented with a six-week history of progressive gastrointestinal signs and was initially diagnosed with acute gastroenteritis with suspected pancreatitis. Initial bloodwork revealed mild hyperglycaemia (243 mg/dL), but fructosamine was unexpectedly low (156 μmol/L), with normal serum albumin and negative urine glucose. Diabetes mellitus (DM) was therefore provisionally excluded. Three weeks later, gastrointes@nal signs had resolved, but blood glucose increased to 314 mg/dL (17.4 mmol/L) and pancreatic lipase to 887 U/L, while fructosamine remained below the diabetic range (224 μmol/L). Abdominal ultrasonography identified concurrent cholangitis, biliary sludge, vacuolar hepatopathy, and enteropathy, consistent with a complex inflammatory gastrointestinal and hepatobiliary process. One week later, persistent hyperglycaemia reached 570 mg/dL, while fructosamine increased to 275 μmol/L but remained within the reference interval. Rapidly evolving DM and altered protein turnover associated with systemic inflammation were considered possible contributors to the discordance. Continuous glucose monitoring (CGM) was subsequently initiated as a longitudinal assessment tool and demonstrated persistent hyperglycaemia, supporting the diagnosis of overt DM. Insulin glargine was initiated and progressively increased from 0.5 to 0.9 U/kg twice daily; however, glycaemic control remained poor. Further investigation for additional contributors to insulin resistance identified a culture-positive Escherichia coli urinary tract infection despite negative urine dipstick leukocyte esterase. Antimicrobial therapy was initiated while insulin therapy was continued. Following treatment, CGM median glucose decreased from >400 mg/dL to approximately 200 mg/dL. This temporal association suggested that the occult urinary tract infection may have contributed to poor glycaemic regulation. Body weight declined by 8.7% during the observation period. Relevance and Novel Information: This case highlights two important diagnostic challenges in canine DM. First, fructosamine may remain within the reference interval despite clinically significant hyperglycaemia, particularly during rapidly evolving disease and concurrent systemic inflammation, and should therefore be interpreted in clinical context. Second, culture-positive urinary tract infection may occur despite negative urine dipstick findings and may contribute to poor glycaemic regulation. The case also demonstrates the practical value of CGM as a longitudinal tool when conventional glycaemic markers are discordant and during insulin titration in veterinary clinical practice.