Pseudomethemoglobinemia: A case report and review of sulfhemoglobinemia

Objectives: To see if methemoglobin could potentially be misdiagnosed and the limitation of present co-oximeters. Patient: A 17-year-old girl who overingested a combination of cimetidine, acetaminophen, ibuprofen, and naproxen in a suicide attempt. Method: Use of pulse co-oximeters to aid in the diagnosis of suspected sulfhemoglobinemia. Results: Diagnosis of sulfhemoglobinemia achieved with final confirmation made with gas chromatography. Patient steadily improved with supportive care. Conclusions: There is a potential for the diagnosis of methemoglobin with some of the limitations of present co-oximeters. The laboratory diagnosis of sulfhemoglobinemia can be difficult to make.