Phenazopyridine-induced sulfhemoglobinemia.

OBJECTIVE: To report a case of sulfhemoglobinemia in a patient receiving phenazopyridine for a urinary tract infection. CASE SUMMARY: A 63-year-old white woman presented to the emergency department with complaints of fatigue and bluish discoloration of her body that had gradually progressed over the previous 6-8 weeks. About 4 months prior to presenting to the emergency department, she had started taking phenazopyridine, an over-the-counter medication for symptoms of dysuria. Because the cyanosis did not improve after the patient received oxygen and methylene blue, sulfhemoglobinemia was suspected and confirmed by spectrophotometer analysis. DISCUSSION: Sulfhemoglobin is a green-pigmented molecule containing a sulfur atom in one or more of the porphyrin rings. It is a rare cause of cyanosis, which is usually drug induced. Sulfhemoglobinemia is suspected when a cyanotic patient has normal to near-normal oxygen tension, laboratory reports of elevated methemoglobin, and does not respond to methylene blue therapy. Sulfhemoglobinemia is relatively rare, despite the widespread use of drugs that have been reported to cause it. Predisposing factors, such as chronic constipation, present in our patient, have been suggested as a source of hydrogen sulfide. CONCLUSIONS: This case of sulfhemoglobinemia, which occurred after the patient took phenazopyridine, is considered a probable adverse event according to the Naranjo probability scale.

Listeria meningitis associated with infliximab.

OBJECTIVE: To report a case of Listeria monocytogenes meningitis in a 73-year-old man receiving infliximab for rheumatoid arthritis. CASE SUMMARY: A 73-year-old white man taking infliximab for rheumatoid arthritis developed listeria meningitis following his second dose. He was receiving other immunosuppressants; however, these remained constant immediately prior to the infection. Diagnosis was confirmed with L. monocytogenes isolated in the cerebrospinal fluid. The patient received 21 days of antibiotic therapy and recovered without any complications. DISCUSSION: L. monocytogenes is a gram-positive, non-spore-forming rod that has been associated with the ingestion of undercooked foods. This organism can cause sepsis or meningitis; however, immunocompromised patients, elderly patients, pregnant women, and neonates appear to be at greater risk for this type of infection. Tumor-necrosis factor-alpha (TNF-alpha) plays an important role in resistance to this type of infection, and listeria infections have been reported in 26 patients receiving TNF-alpha inhibitors. In our patient, the listeria infection occurred following his second course of infliximab, which provides a temporal relationship between the listeria infection and infliximab. However, his underlying rheumatoid arthritis and chronic steroid therapy would also increase his risk for a listeria infection. CONCLUSIONS: The listeria infection in our patient was a possible adverse event of infliximab according to the Naranjo probability scale. Because the majority of listeria infections occur in patients who are immunosuppressed, it would be reasonable to provide education for healthcare professionals on preventing these infections in all patients receiving immunosuppressants, including anti-TNF-alpha therapy. Those at risk due to their underlying health conditions should also be monitored closely.