An Ashkenazi Jewish woman presenting with favism

Favism: Clinical Features at Different Ages

Favism is a hemolytic disease due to the ingestion of fava beans in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency. There is wide inter- and intra-individual variability in the development of hemolytic crisis, and several factors influence it: quantity, quality, ripeness of fava beans, and age of onset. In this narrative review of case reports and case series, we reported the predisposing factors and clinical features for four different age groups classified as follows: pregnant women and infants (i.e., exclusively breastfed children); children, from weaned to 11 years; preadolescents and adolescents, from 11 to 18 years; and adults (18 years and older). Some symptoms developed only in specific age groups: death in infants; visual impairment in children; systolic murmur in infants, children, and adolescents; and renal failure in adults. In youngest children or pregnant women the severity is the highest. Some other symptoms were present in all: jaundice, increased bilirubin, splenomegaly, hepatomegaly, discolored urine, tachycardia, pallor, abdominal pain, malaise, vomit, nausea, and dizziness. Laboratory findings are characterized by anemia, reticulocytosis, elevated bilirubin level, and sometimes urinary urobilinogen and methemoglobinemia. In most cases the symptomatology is self-limited and does not release sequelae, but hospitalization and transfusion are often required.

Favism: A Case Report

Favism is an acute hemolytic syndrome that occurs in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency following the ingestion of fava beans. Diagnosis can be challenging because the severity of hemolytic anemia varies among this patient population. Furthermore, the severity of hemolytic episodes can vary in the same patient. The diagnosis of G6PD deficiency and patient education pertaining to safe and unsafe medications and foods are crucial to prevent the reoccurrence of hemolytic episodes. Here, we report the case of a man admitted to our hospital with an acute hemolytic episode. At the time of admission, we were unaware that he had ingested fava beans and only discovered that he had G6PD deficiency while performing complementary studies during the hemolytic crisis to determine its etiology.

High resolution melting curve analysis enables rapid and reliable detection of G6PD variants in heterozygous females

Background

Like glucose-6-phosphate dehydrogenase (G6PD) deficient hemizygous males and homozygous females, heterozygous females could also manifest hemolytic crisis, neonatal hyperbilirubinemia or kernicterus upon exposure to oxidative stress induced by certain foods such as fava beans, drugs or infections. Although hemizygous males and homozygous females are easily detected by conventional G6PD enzyme assay method, the heterozygous state could be missed by the conventional methods as the mosaic population of both normal and deficient RBCs circulates in the blood. Thus the present study aimed to apply high resolution melting (HRM) curve analysis approach to see whether HRM could be used as a supplemental approach to increase the chance of detection of G6PD heterozygosity.

Results

Sixty-three clinically suspected females were evaluated for G6PD status using both enzyme assay and HRM analysis. Four out of sixty-three participants came out as G6PD deficient by the enzyme assay method, whereas HRM approach could identify nine participants with G6PD variants, one homozygous and eight heterozygous. Although only three out of eight heterozygous samples had G6PD enzyme deficiency, the HRM-based heterozygous G6PD variants detection for the rest of the samples with normal G6PD enzyme activities could have significance because their newborns might fall victim to serious consequences under certain oxidative stress.

Conclusions

In addition to the G6PD enzyme assay, HRM curve analysis could be useful as a supplemental approach for detection of G6PD heterozygosity.

Glucose-6-phosphate dehydrogenase deficiency: not exclusively in males

Glucose‐6‐phosphate (G6PD) deficiency is the most common human enzyme defect, often presenting with neonatal jaundice and/or acute hemolytic anemia, triggered by oxidizing agents. G6PD deficiency is an X‐linked, hereditary disease, mainly affecting men, but should also be considered in females with an oxidative hemolysis.

Glucose-6-phosphate dehydrogenase deficiency and severe neonatal hyperbilirubinemia: a complexity of interactions between genes and environment

Glucose-6-phosphate dehydrogenase deficiency is a commonly occurring genetic condition, likely to be encountered today in virtually any corner of the globe. Sudden episodes of hemolysis associated with the condition may result in exponential increases in serum total bilirubin concentrations to levels at which bilirubin-induced neurologic damage may occur. The hyperbilirubinemia is the result of complex interactions between genes and environment. Neonatal screening programs coupled with parental and medical caretaker education may be successful in limiting the severity of disease.

An audit of the precipitating factors for haemolytic crisis among glucose-6-phosphate dehydrogenase-deficient paediatric patients

Background

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common genetic enzyme deficiencies leading to haemolytic anaemia. This study aimed to investigate the precipitating factors for haemolytic crisis in G6PD-deficient paediatric patients in Jordan.

Method

A retrospective study of data from the records of 258 paediatric patients admitted to a major paediatric hospital in North Jordan from January 2001 until April 2007. Patients included were G6PD-deficient children who were admitted to the hospital secondary to an episode of haemolytic anaemia.

Results

Of 258 paediatric patients, 244 (94.2%) had developed a haemolytic episode secondary to ingestion of fava beans. The remaining 14 children (5.8%) developed a haemolytic episode triggered by other factors, such as drugs and upper respiratory infections.

Conclusion

Fava bean ingestion is the major precipitating factor for haemolytic anaemia episodes among G6PD-deficient children in Jordan.

Fatal kernicterus in a girl deficient in glucose-6-phosphate dehydrogenase: a paradigm of synergistic heterozygosity

A 6-day-old female newborn, readmitted for extreme hyperbilirubinemia with bilirubin encephalopathy, died despite 2 double-volume exchange transfusions. On autopsy examination the basal ganglia and hippocampus were selectively stained deep yellow. The infant was heterozygous for both the glucose-6-phosphate dehydrogenase Mediterranean mutation and for the (TA)(6)/(TA)(7) promoter polymorphism for the gene encoding the bilirubin conjugating enzyme uridine diphosphate-glucuronosyltransferase 1A1 (UGT1A1*28, associated with Gilbert syndrome). No additional mutations of the UGT1A1 were detected. Seemingly innocuous, heterozygotic mutations may interact synergistically to result in serious and even fatal outcomes.

Antioxidant vitamins and glucose-6-phosphate dehydrogenase deficiency in full-term neonates

OBJECTIVE

The mechanism by which glucose-6-phosphate dehydrogenase (G6PD) deficiency causes neonatal hyperbilirubinemia is not completely understood. However, the genetic disorder G6PD deficiency predisposes red blood cells to oxidative stress. The aim of this study was to establish the relationship between plasma antioxidant vitamin (E and C) levels and the development of hyperbilirubinemia in full-term neonates with deficient G6PD.

METHODS

A total of 196 live birth neonates of healthy mothers were included in this study. Twelve of them were deficient in G6PD. In addition to demographic data, serum total bilirubin, hemoglobin, hematocrit, and vitamin E and C levels were measured on the first day after birth.

RESULTS

Neonates with G6PD deficiency (n=7) who did not develop hyperbilirubinemia (mean serum bilirubin level of 70.8+/-23 micromol/l, median 71.8) and neonates with G6PD deficiency (n=4) who developed hyperbilirubinemia (mean serum bilirubin level of 226.7+/-79 micromol/l, median 233.4) on the first day of life had similar gestational weights and age. The second group, however, had lower hemoglobin and hematocrit as well as plasma vitamin C and E levels. None of these results showed significant difference.

CONCLUSION

The results of the present study indicate that red blood cell hemolysis as a result of inadequate antioxidants system in G6PD-deficient neonates is not the only contributing factor for hyperbilirubinemia.

Glucose-6-phosphate dehydrogenase deficiency

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzyme defect, being present in more than 400 million people worldwide. The global distribution of this disorder is remarkably similar to that of malaria, lending support to the so-called malaria protection hypothesis. G6PD deficiency is an X-linked, hereditary genetic defect due to mutations in the G6PD gene, which cause functional variants with many biochemical and clinical phenotypes. About 140 mutations have been described: most are single base changes, leading to aminoacid substitutions. The most frequent clinical manifestations of G6PD deficiency are neonatal jaundice, and acute haemolytic anaemia, which is usually triggered by an exogenous agent. Some G6PD variants cause chronic haemolysis, leading to congenital non-spherocytic haemolytic anaemia. The most effective management of G6PD deficiency is to prevent haemolysis by avoiding oxidative stress. Screening programmes for the disorder are undertaken, depending on the prevalence of G6PD deficiency in a particular community.