Naphthalene and hemolytic anemia: a possible association in a black infant with glucose-6-phosphate dehydrogenase deficiency presenting with suspected heart failure.

Introduction Deficiency of glucose-6-phosfate dehydrogenase (G6PD) is a X-linked recessive disease characterized by susceptibility to hemolysis due to low or undetectable enzime levels. The reduction of the enzime activity impairs red blood cell toleration of oxidative stress. Clinical presentation depends on the variant of the disease: the Mediterranean variant presents often with acute severe hemolysis; in black populations hemolysis is usually mild and chronic. In both the cases oxidant drugs have been implicated in the etiology of the hemolytic events. Naphthalene, commonly used at home for clothes storage, was firstly related with hemolysis in G6PD deficiency in 1964 because of its oxidative properties. In the following years the association of naphthalene domestic use and hemolysis in G6PD deficiency was confirmed in numerous cases, both for ingestion and inhalation. Case report Nigerian female infant diagnosed with G6PD deficiency at born. She remained well until the age of 40 days when she was admitted to the hospital because of feeding difficulty, vomiting and mild respiratory distress in the last 4 days. Physical examination revealed HR 180 bpm, RR 60 breaths/min, mid-systolic cardiac murmur to the precordium, sO2 97%; respiratory, abdominal and neurological examination was normal. The infant was breastfed and she did not assume drugs, fava beans or other agents of hemolysis in G6PD. Her hemoglobin was 9 mg/dl (vs 12.6 mg/dl 30 days before), hematocrit 29.5%, reticulocytes 145000/mmc (5%); aptoglobin <6. The serum bilirubin was 1.3 mg/dl (direct 0.4 mg/dl). Diagnostic workup included lactate and ammonia dosage (normal), venous blood gases sample (normal), Coombs test (negative), fecal occult blood test (negative), ECG (consistent with age), ECHOCARDIOGRAM (normal), THORACIC X-RAY (normal), ABDOMINAL and CEREBRAL US (normal). A strong smell of naphthalene was noted at the infant's bedside; parents reported they were used to put numerous naphthalene-containing mothballs in their and their girl's closets. In the following days infant's clinical conditions progressively improved without specific treatment, with adequate weight increase, reduction of sistolic murmur, normalization of feeding. Complete elimination of naphthalene was recommended. Two months later a blood sample demonstrated Hb 9.6 g/dl, reticulocyte 104000/mmc; nowadays the child is completely asymptomatic. Conclusion Once excluded heart failure and metabolic disease, we hypothesized that infant's symptoms could be completely explained by acute hemolysis (probably happened before the hospital admission) and the consequent anemia. Ruled out blood loss and immune red cells consumption, G6PD deficiency related hemolysis remained the most probable etiology for the anemia and the inhalation of naphthalene the more likely precipitating agent. In conclusion naphthalene inhalation should be suspected in infants with G6PD deficiency presenting with typical or atypical signs of hemolysis.