Immeasurable levels of serum phosphate--an unidentified cause of respiratory failure in a diabetic patient.

We report a case of immeasurable levels of serum phosphate in a patient with juvenile type Diabetes mellitus and diabetic ketoacidosis who developed respiratory failure. A 27-year-old female with juvenile type insulin-dependent Diabetes mellitus was admitted because of suspected acute mediastinitis and respiratory failure, probably, among other responsible factors, caused and complicated by undetectable levels of serum phosphate. The serum phosphate concentration three days after aggressive treatment was only 0.2 mmol/L. Furthermore, a significant improvement in weakness and lethargy was observed. To the best of our knowledge, this is the first described case of immeasurable levels of serum phosphate. In patients with Diabetes mellitus, serum phosphate concentrations should be routinely checked in order to avoid additional complications.