Patent urachus and associated comorbidities in 101 newborn foals : a retrospective study

Abstract

Background: Patent urachus is a common disease in newborn foals. However, despite its frequency, studies investigating symptoms, comorbidities, treatment and prognosis in a large number of affected foals have rarely been conducted. Objective: This study aimed to describe the clinical symptoms, laboratory diagnostic findings and prognosis of foals with patent urachus. Method: Data from 101 foals with a patent urachus from 2006 to 2017 were analysed. Results: Patent urachus occurred at a frequency of 7.8% of all foals up to the 14th day of life during the study period. More colts (74.3%) than fillies (25.7%) were affected. In those with secondary urachal fistulae, patent urachus (91.1%) was significantly more diagnosed than persistent urachus (8.9%). Typical symptoms were a moist external umbilical environment (100%) and urine dripping from the external umbilical cord remnant during urination (75%). The average age at the time of diagnosis was 5.5 ± 3.2 days (median: 5 days, range: <1–13 days). Umbilical resection was performed in 29.7% of foals, whereas 70.3% were treated conservatively. In total, 67.3% of affected foals were discharged from the clinic. Foals that underwent umbilical resection were discharged in 76.7%, and those that underwent conservative treatment in 63.4% of cases. No typical laboratory diagnostic findings related to patent urachus could be determined. However, an elevated lactate concentration on the day of admission was linked to significantly worsened prognosis (p = 0.021). In 18.5% of the foals, which received surgery, a wound-healing complication occurred at the abdominal suture. Further, 67% of the foals had one or more comorbidities. The presence of musculoskeletal disorders significantly worsened the survival prognosis (p = 0.037). In total, 46 foals were monitored for at least 6 months (6 months to 10 years) after discharge from the clinic. At this point, 93.9% of the foals were alive, and none developed any further health complications with the umbilicus or abdominal sutures. Conclusion: The primary result of this article is that patent urachus has a limited statistical influence on clinical parameters, laboratory values and prognosis. Comorbidities and/or sequelae worsen survival prognosis. The prognosis in the first 6 months after discharge was very good.