M. Narayanaswamy1, Sonali Appaiah2, Nagappa H. Handargal3

BACKGROUND: The correlation of serum phosphorus levels in DKA with prognosis of patient remains controversial; we prospectively evaluated the correlation in 50 consecutive patients with DKA.

METHODS: This study was done on patients of DKA admitted to Victoria & Bowring & Lady Curzon hospitals attached to Bangalore Medical College, Bangalore. The total duration of the study was 2 years. A total of 50 patients of DKA were taken into the study. The diagnosis of DKA was based on ADA criteria. Venous blood samples were obtained from each patient and serum phosphorous levels were estimated at admission, day 2 and on day of improvement and discharge or at worsening /death of the patient. The correlation of serum phosphorus levels in DKA with prognosis of patient was studied using the One-Way Analysis of Variance test and Fisher LSD test

RESULTS: Type 1 DM constituted 30% while type 2DM made up 70% of the study group. In type 1 DM 53% were in the age group 18-28, while 47% were 29- 38 in age group range. In type 2DM maximum patients were in age group 39-48 yrs accounting about 40%; 28% in range 49-58yrs and 29% in range >59yrs. In type 1 DM the most common precipitating cause of DKA was infection and noncompliance each accounting for 41%, with new onset DM seen in 18% of patients. In type 2 DM infection was the most common cause accounting for 42%, closely followed by noncompliance to treatment which came up to 41% of the patients of the precipitating infections UTI was the most common cause around 33%, while pneumonia accounted for 19%. The mean duration of hospitalization of DKA patients was 6.2days. On day 0, 72% of population had normal or high values of Phosphorous and hypophosphatemia was seen in 28% had hypophosphatemia at admission. On Day 2 of admission, incidence of hypophosphatemia increased to 69%. At discharge phosphorous values returned to normal with 95% of patients having normal levels. Significant correlation was observed in phosphorous levels in DKA patients between phosphorous levels on day 2 and phosphorous levels at discharge in type 1 and 2 DM. In study group 10% mortality was seen. Type 2 DM patients accounted for 80%, while Type 1DM patients accounted for 20% of the mortality. Among patients with DKA at death, hypophosphatemia was seen 60%. No significant correlation was observed between phosphorous level and duration of stay of patient in hospital. Significant correlation was observed between phosphorous level at Day discharge/Death and outcome of the patient i.e., recovery or death of the patient with point estimation values of 0.086 (CI= 0.008 – 0.93).

CONCLUSION: The correlation of the serum phosphorous and prognosis of patient during hospital stay was significant as shown in our study and other studies as well. Hypophosphatemia is commonly encountered at diagnosis and during treatment of a patient with DKA. Serum phosphate levels do not accurately reflect intracellular phosphorus stores; hence symptoms may be present even with mild or moderate hypophosphatemia. The assessment of the serum phosphorous of these patients during treatment could be a useful predictor of the clinical outcome in DKA. With the high prevalence of hypophosphatemia in DKA, and risk for poor prognosis in such patients, frequent laboratory monitoring is recommended, especially in high-risk groups