Sulfhemoglobinemia

Sulfhemoglobinemia
SpecialtyHematology
SymptomsCyanosis, urinary tract infection and chronic constipation
ComplicationsHypoxemia, methemoglobinemia, and hypoxia
Duration100-120 days (lifespan of red blood cells)
CausesSulfur medications such as phenacetin, metoclopramide, dapsone, phenzopyridine, and trimethoprim-sulfamethoxazole; hydrogen-sulfide-producing intestinal bacteria, such as Morganella morganii
Risk factorsPulmonary arteriovenous malformation
PreventionAvoidance of sulfur-containing compounds including drugs
TreatmentBlood transfusions

Sulfhemoglobinemia is a rare condition in which there is excess sulfhemoglobin (SulfHb) in the blood. The pigment is a greenish derivative of hemoglobin which cannot be converted back to normal, functional hemoglobin. It causes cyanosis even at low blood levels.

It is a rare blood condition in which the β-pyrrole ring of the hemoglobin molecule has the ability to bind irreversibly to any substance containing a sulfur atom. When hydrogen sulfide (H2S) (or sulfide ions) and ferrous ions combine in the heme of hemoglobin, the blood is thus incapable of transporting oxygen to the tissues.