Assessment of Direct Costs of Admission Due to Presumed Microbial Keratitis in a Tertiary Referral Hospital in Thailand: A 7-Year Retrospective Study.

Objective: To evaluate the direct healthcare cost of admission and examine the effects of cost drivers of treating presumed microbial keratitis (MK) at a tertiary referral hospital. Design: Retrospective study. Methods: A total of 741 patients who presented with MK were included. All information regarding costs was collected, and demographic data were employed for risk factor analysis. Results: The total cost of treating MK over a 7-year period at Rajavithi Hospital was US$14,514,625.04, while the median cost was US$10,840.17 per patient (Q1-3, US$5866.56-24,172.28). The medical professional services were the highest cost category in terms of both total cost of treatment over 7 years and median cost per patient, accounting for US$6,474,718.43 and US$5235.20 (Q1-3, US$2582.79-10,474.24) respectively. In 2020, the total cost of treatment declined, corresponding with fewer hospitalized patients; however, the median cost per patient was the highest of all years, amounting to US$15,089.90 (Q1-3, US$8064.17-29102.50), while the median cost per patient from 2014 to 2019 was US$9969.96 (Q1-3, US$5177.98-21,942.68). Statistical significance was found in the median cost per patient in 2020 compared to the median cost per patient in 2014-2019 (p-value 0.019). Risk factors associated with the more expensive cost of treatment were longer length of stay (LOS); age more than 60 years old; readmission; diabetes mellitus (DM); hypertension; and heart disease. Conclusion: There were several key factors impacting the direct healthcare costs of severe MK treatment. Medical professional services emerged as the most substantial cost category, while longer hospital stays, older age groups, readmission cases, and comorbidities such as diabetes mellitus, hypertension, and heart disease were all linked to elevated treatment expenses. There were no statistically significant differences in the direct medical expenses during hospitalization associated with treating severe MK, whether the culture results were positive or negative, or regardless of the type of cultured organism utilized.