Technical evaluation and usability of a quantitative G6PD POC test in cord blood: a mixed-methods study in a low-resource setting.

OBJECTIVES: New point-of-care (POC) quantitative G6PD testing devices developed to provide safe radical cure for Plasmodium vivax malaria may be used to diagnose G6PD deficiency in newborns at risk of severe neonatal hyperbilirubinaemia, improving clinical care, and preventing related morbidity and mortality. METHODS: We conducted a mixed-methods study analysing technical performance and usability of the 'STANDARD G6PD' Biosensor when used by trained midwives on cord blood samples at two rural clinics on the Thailand-Myanmar border. RESULTS: In 307 cord blood samples, the Biosensor had a sensitivity of 1.000 (95% CI: 0.859 to 1.000) and a specificity of 0.993 (95% CI: 0.971 to 0.999) as compared with gold-standard spectrophotometry to diagnose G6PD-deficient newborns using a receiver operating characteristic (ROC) analysis-derived threshold of ≤4.8 IU/gHb. The Biosensor had a sensitivity of 0.727 (95% CI: 0.498 to 0.893) and specificity of 0.933 (95% CI: 0.876 to 0.969) for 30%-70% activity range in girls using ROC analysis-derived range of 4.9-9.9 IU/gHb. These thresholds allowed identification of all G6PD-deficient neonates and 80% of female neonates with intermediate phenotypes.Need of phototherapy treatment for neonatal hyperbilirubinaemia was higher in neonates with deficient and intermediate phenotypes as diagnosed by either reference spectrophotometry or Biosensor.Focus group discussions found high levels of learnability, willingness, satisfaction and suitability for the Biosensor in this setting. The staff valued the capacity of the Biosensor to identify newborns with G6PD deficiency early ('We can know that early, we can counsel the parents about the chances of their children getting jaundice') and at the POC, including in more rural settings ('Because we can know the right result of the G6PD deficiency in a short time, especially for the clinic which does not have a lab'). CONCLUSIONS: The Biosensor is a suitable tool in this resource-constrained setting to identify newborns with abnormal G6PD phenotypes at increased risk of neonatal hyperbilirubinaemia.

[Congenital hemolytic anemias due to erythrocyte membrane and enzyme defects]. / Kongenitale hämolytische Anämien durch Membran- und Enzymdefekte der Erythrozyten.

Erythrocyte membrane and enzyme defects are the most common cause of congenital hemolytic anemias in the Central European population. Diagnostics include erythrocyte morphology, special biochemical tests such as osmotic fragility (AGLT) and EMA. For enzymopenic hemolytic anemias, cost-effective biochemical analysis remains the gold standard, supplemented by molecular genetic diagnostics when appropriate. Therapeutically, near complete splenectomy reduces hemolysis significantly for spherocytosis. The residual spleen at least provides a considerable phagocytic function and better response to immunisation and by inference possibly better protection against severe post-splenectomy infection. For pyruvate kinase deficiency, which is not so rare, a new molecular therapy (Mitapivat) is currently being introduced. In G6PD deficiency, there are very few drugs that cause hemolytic crisis. Sudden onset of hemoglobinuria is an early important hallmark of severe hemolytic crisis in G6PD deficiency and these patients should be hospitalized. Aplastic crises in the setting of parvovirus B19 infection occur in all congenital hemolytic anemias. Transfusion is not preventable in most cases. Iron-excreting treatment is required in the rare patients in need of chronic transfusion.

Acalypha indica -induced transient glucose-6-phosphate dehydrogenase deficiency with acute haemolysis.

Acalypha indica is a tropical herb found in Asia. The entire plant, especially the leaves, is used in herbal medicine for several therapeutic purposes. Acute intravascular haemolysis and methaemoglobinaemia have been reported in patients who consume this herb. We present a case of a previously healthy middle-aged man who ingested boiled leaves of A. indica The patient developed clinical symptoms and signs of intravascular haemolysis 7 days after ingestion. Peripheral blood smear showed typical findings of glucose-6-phosphate dehydrogenase (G6PD) deficiency with acute haemolysis. The G6PD activity was low during active haemolysis. The G6PD level, however, returned to normal after 4 months of follow-up. The patient was further tested for common G6PD gene mutations in Southeast Asia and was negative. Ingestion of A. indica may induce transient G6PD deficiency, which in this patient led to acute haemolysis and methaemoglobinaemia.

G6PD Deficiency Prevalence as a Cause of Neonatal Jaundice in a Neonatal Ward in Dohuk, Iraq.

OBJECTIVE: The current study initiated to address the effect of glucose-6-phosphate dehydrogenase (G6PD) deficiency on the pathogenesis and the severity of neonatal hyperbilirubinemia (NHB). STUDY DESIGN: A total of 100 newborns with moderate to severe indirect hyperbilirubinemia and 50 normal neonates without hyperbilirubinemia had been enrolled in the current case-control study. All enrolled neonates had been tested for ABO and Rh(D) blood grouping, Total serum bilirubin measurement, complete blood count, morphology, reticulocyte counts, direct Coombs' test, and G6PD enzyme assay. RESULTS: From all enrolled hyperbilirubinemic neonates, 16% were G6PD deficient and this displays a statistically significant difference in comparison to controls (only 6% were G6PD deficient). Also, significant difference was found in the level of serum indirect bilirubin among G6PD-deficient neonate in comparison to G6PD nondeficient neonates which had contributed significantly to the difference in the duration of phototherapy and hospitalization among deficient neonate. Despite this, no significant difference found in the onset of presentation, reticulocytes count, and age of neonates between the two groups (G6PD-deficient and G6PD nondeficient neonates). CONCLUSION: The current study augments the etiological role of G6PD in the causation and severity of NHB in the region; however, in the absence of significant difference in the reticulocytes and the hemoglobin level, the underlying mechanism cannot be backed to the excess hemolysis alone.

High dose vitamin C induced methemoglobinemia and hemolytic anemia in glucose-6-phosphate dehydrogenase deficiency.

Investigational use of intravenous vitamin C has been on the rise, but its side effects may be underreported. A 75-year-old woman presented with acute onset of jaundice, dark urine and shortness of breath after receiving 30 g of vitamin C infusion as an unconventional therapy for her hemifacial spasm. Diagnosis of methemoglobinemia and hemolytic anemia was made clinically and confirmed on laboratory tests. She recovered with supportive treatment and packed cell transfusion. Her previously unrecognised underlying condition of glucose-6-phosphate dehydrogenase (G6PD) deficiency was confirmed months after the initial presentation. This is the first reported case of methemoglobinemia and hemolytic anemia induced by high dose vitamin C in a female patient with G6PD deficiency. The dosage of vitamin C administered was also relatively low compared with previous adult reports. When administered at physiological dose, vitamin C can be used as an alternative to methylene blue in treatment of methemoglobinemia in patients with G6PD deficiency. However at supraphysiological dose vitamin C can paradoxically lead to hemolytic anemia in the same group of patients. Physicians should be alert of these potential complications of high dose vitamin C.

Sickle cell screening in Uganda: High burden, human immunodeficiency virus comorbidity, and genetic modifiers.

BACKGROUND: The Uganda Sickle Surveillance Study provided evidence for a large sickle burden among HIV-exposed infants in Uganda. To date, however, no large scale screening program has been developed for Central or East Africa. METHODS: A 3-year targeted sickle cell screening project in Uganda was designed by the Ministry of Health to (1) determine sickle cell trait and disease prevalence within high-burden districts, (2) document the prevalence among HIV-exposed and nonexposed children, (3) confirm previously suggested HIV comorbidity, and (4) estimate the co-inheritance of known genetic modifiers of sickle cell disease. RESULTS: A total of 163 334 dried blood spot samples collected between April 2015 and March 2018 were analyzed, including 112 352 samples within the HIV Early Infant Diagnosis program. A high burden with >1% sickle cell disease was found within targeted East Central and Mid-Northern districts, in both HIV-exposed and nonexposed children. Based on crude birth-rate data, 236 905 sickle cell trait births and 16 695 sickle cell disease births will occur annually in Uganda. Compared to sickle cell disease without HIV, the odds ratio of having sickle cell disease plus HIV was 0.50 (95% confidence interval = 0.40-0.64, P < .0001). Alpha-thalassemia trait and G6PD deficiency were common with sickle cell disease, but with different geospatial distribution. CONCLUSIONS: High sickle cell burden and potential HIV comorbidity are confirmed in Uganda. Genetic modifiers are common and likely influence laboratory and clinical phenotypes. These prospective data document that targeted sickle cell screening is feasible and effective in Uganda, and support development of district-level comprehensive care programs.

[How I do in front of an hemolytic anemia of unknown etiology?] / Que faire devant une anémie hémolytique sans étiologie retrouvée ?

The most frequent causes of hemolytic anemias are immune or infectious diseases, drug induced hemolysis, thrombotic microangiopathies, hereditary spherocytosis, glucose-6-phosphate dehydrogenase or pyruvate kinase deficiencies, thalassemia's and sickle cell disease. Sometimes no cause is found because a rarer etiology is involved. The goal of this review is to remember some unfrequent constitutional or acquired causes and to point out difficulties to avoid wrong interpretations of analysis results.

A vegetable-induced hemolytic crisis in a G6PD deficient person: a case report.

BACKGROUND: Hemolysis can occur in people with G6PD deficiency under oxidative stress. Acalypha indica is a tropical plant used as a medicinal plant as well as a vegetable. There are a few reported cases of Acalypha indica ingestion induced hemolysis in G6PD deficient people. All except one of them are from Sri Lanka. The information available at present (2017) about G6PD deficiency prevalence and variants of the G6PD gene among Sri Lankans is very sparse. There are no past reports on hemolytic crisis in a G6PD deficient person presenting mimicking leptospirosis. CASE PRESENTATION: A middle-aged Sri Lankan man presented on the third day of illness complaining of fever, head ache, arthralgia, myalgia, abdominal pain, vomiting, passing dark urine and reduced of urine volume. He gave a history of possible exposure to leptospirosis. He was pale, icteric and his liver was palpable 1 cm below costal margin and there were no other remarkable findings upon physical examination. He had neutrophilic leucocytosis. Leptospirosis was diagnosed. During the second assessment we noticed he was very pale and his urine sample pointed towards hemoglobinuria. Further questioning revealed he had consumed leaves of Acalypha indica as a vegetable. Acute hemolysis in a G6PD deficient patient following Acalypha indica ingestion was diagnosed. Blood transfusions were given to correct his anemia. Later, Brewer's test and quantitative assay of G6PD levels confirmed the diagnosis of G6PD deficiency. CONCLUSIONS: A hemolytic crisis following oxidative stresses in G6PD deficient patients can present mimicking leptospirosis. Further investigations may reveal why the great majority of cases of acute hemolysis in G6PD deficient person following Acalypha indica ingestion are from Sri Lanka.

[G6PD deficiency in females with neonatal revelation. Report of four cases]. / Déficit en G6PD chez la fille à révélation néonatale. Revue de 4 cas cliniques.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human erythrocyte enzyme defect, estimated to affect approximately 4 million people worldwide. It is associated with severe neonatal hyperbilirubinemia, which may lead to bilirubin encephalopathy and kernicterus, and with hemolytic crisis. G6PD deficiency is an X-linked enzymopathy affecting hemizygous males, homozygous females, and also a subset of heterozygous females via chromosome X inactivation. We report four cases of female newborns with neonatal hyperbilirubinemia related to a G6PD deficiency and followed by the Centre national de référence en hémobiologie périnatale (CNRHP) from November 2013 to July 2014. Clinical and biological characteristics suggested G6PD deficiency (jaundice observed within the first 24h, severe hyperbilirubinemia, associated with regenerative hemolytic anemia, low response to phototherapy, ethnic origin of the parents from high-incident geographical regions). The family investigations revealed a deficit in G6PD in one of the parents who was unaware of this deficit until then. This article aims to make neonatologists and pediatricians aware of the need to search for an etiology for any severe hyperbilirubinemia and to raise G6PD deficiency in male and female newborns in case of hyperbilirubinemia with hemolysis.

Rasburicase-Induced Methemoglobinemia in a Patient with Glucose-6- Phosphate Dehydrogenase Deficiency.

BACKGROUND: Rasburicase is commonly used in patients with hematologic malignancies for tumor lysis syndrome prophylaxis and management. Methemoglobinemia is a serious rare adverse effect of rasburicase, more common in patients with G6PD deficiency. Prompt diagnosis and appropriate management of this condition can make the difference between successful recovery and significant morbidity. Here we discuss the link of rasburicase with methemoglobinemia and the pathophysiology behind increased incidence of this side effect in G6PD deficient patients. METHODS: We report the case of a 73-year-old African American man who developed methemoglobinemia on rasburicase treatment, who was later confirmed to be G6PD deficient. We reviewed the literature using Pubmed and Google Scholar using the following key words: "methemoglobinemia", "rasburicase", "urate oxidase", tumor lysis syndrome", G6PD deficiency", "hemolytic anemia" and "hyperuricemia". RESULTS: Rasburicase-induced methemoglobinemia is more common in patients with G6PD deficiency, and rasburicase is therefore contraindicated in these patients. Clinical presentation includes cyanosis, pallor, methemoglobin levels of 8-12%, and oxygen saturation gap which is evident from ABG analysis, though pulse oximetry is normal. Treatment consists of oxygen supplementation, ascorbic acid and blood transfusion. Importantly, methylene blue is avoided as therapy in G6PD deficiency as it can worsen the methemoglobinemia. CONCLUSION: Rasburicase-induced methemoglobinemia is a serious concern, especially in African- American patients. It should be considered when clinical signs and symptoms are present. Knowledge of this side effect is important in early diagnosis and successful management of the condition.

Déficit de glucosa-6-fosfato deshidrogenasa: la peregrinación del chico con color / Glucose 6-phosphate-dehydrogenase deficiency: the long tour of the colored boy

El déficit de glucosa-6-fosfato-deshidrogenasa es la enzimopatía más frecuente de los glóbulos rojos. Se trata de una enfermedad ligada al cromosoma X que afecta preferentemente a varones. La prevalencia es de alrededor de 400 millones de personas en el mundo. Pese a esto, se considera una enfermedad "huérfana" en tratamientos y actos médicos necesarios, como la anestesia. Presentamos el caso de un paciente afecto de esta mutación y su periplo por distintas especialidades para lograr una extracción dentaria con anestesia local (AU)

Glucose 6-phosphate-dehydrogenase deficiency is the most common enzymatic disease of red blood cells. This is an X-linked disorder that mainly affects males. The prevalence is about 400 million people worldwide. Despite of this, it is considered an orphan disease in some treatments and medical procedures such as anesthesia. We describe the case of a 9-year-old male patient affected by this mutation and his travel around different specialists in order to achieve a dental extraction under local anesthesia (AU)

Severe G6PD Deficiency Due to a New Missense Mutation in an Infant of Northern European Descent.

We report a term male infant born to parents of Danish descent, who on the second day of life developed jaundice peaking at 67 hours and decreasing on applied double-sided phototherapy. In the weeks following, the infant showed signs of ongoing hemolysis. Laboratory tests showed very low glucose-6-phosphate dehydrogenase (G6PD) enzymatic activity, and sequencing of the G6PD gene revealed a previously uncharacterized missense mutation c. 592 C>A (Arg198Ser). Oral DNA from the infant had the same G6PD mutation, suggesting a spontaneous maternal germline mutation as the mutation was not observed in leukocytes from the mother.

Glucose-6-Phosphate Dehydrogenase Screening in Israel-Arab and Palestinian-Arab Neonates.

OBJECTIVE: To evaluate the frequency of glucose-6-phosphate dehydrogenase (G-6-PD) deficiency, the incidence of clinically significant jaundice (any serum total bilirubin value >75th percentile on the hour-specific bilirubin nomogram), and the need for phototherapy in the pooled male Israeli-Arab and Palestinian-Arab population born at the Shaare Zedek Medical Center in Jerusalem, Israel. STUDY DESIGN: Quantitative G-6-PD enzyme testing of umbilical cord blood was performed during birth hospitalization. G-6-PD deficiency was defined as any G-6-PD value <7.0 U/gHb. Transcutaneous bilirubin was performed daily during birth hospitalization, with serum total bilirubin testing in those with a transcutaneous bilirubin value >75th percentile. RESULTS: Ten of 286 (3.5%) consecutively delivered male Arab newborns had G-6-PD deficiency. Clinically significant jaundice was higher in the population with G-6-PD deficiency compared with normal controls (relative risk, 3.45; 95% CI, 1.24-9.58). Thirty percent of the newborns with G-6-PD deficiency met American Academy of Pediatrics indications for phototherapy according to the high-risk (middle) curve on the phototherapy graph. CONCLUSION: The frequency of G-6-PD deficiency in the Arab neonatal population delivering at this medical center meets World Health Organization criteria for neonatal G-6-PD screening (3%-5%). As in other ethnic groups, clinically significant jaundice is more frequent in newborns of this ethnic group with G-6-PD deficiency compared with G-6-PD-normal controls. Neonatal G-6-PD screening for both males and females of this population subgroup, in conjunction with parental education regarding the dangers of the condition and its prophylaxis, has now been incorporated into our institution's routine G-6-PD screening program.

Early neonatal bilirubin, hematocrit, and glucose-6-phosphate dehydrogenase status.

OBJECTIVE: To document the patterns of bilirubin and hematocrit values among glucose-6-phosphate dehydrogenase (G6PD)-deficient and G6PD-normal Nigerian neonates in the first week of life, in the absence of exposure to known icterogenic agents. METHODS: The G6PD status of consecutive term and near-term neonates was determined, and their bilirubin levels and hematocrits were monitored during the first week of life. Infants were stratified into G6PD deficient, intermediate, and normal on the basis of the modified Beutler's fluorescent spot test. Means of total serum bilirubin (TSB) and hematocrits of the 3 groups of infants were compared. RESULTS: The 644 neonates studied comprised 353 (54.8%) boys and 291 (45.2%) girls and 540 (83.9%) term and 104 (16.1%) near-term infants. They consisted of 129 (20.0%) G6PD-deficient, 69 (10.7%) G6PD-intermediate, and 446 (69.3%) G6PD-normal neonates. The G6PD-deficient and G6PD-intermediate infants had higher mean TSB than their G6PD-normal counterparts at birth and throughout the first week of life (P < .001). Mean peak TSB levels were 14.1 (9.48), 10.2 (3.8), and 6.9 (3.3) mg/dL for G6PD-deficient, G6PD-intermediate, and G6PD-normal neonates, respectively. Peak TSB was attained on approximately day 4 in all 3 groups, and trends in TSB were similar. Mean hematocrits at birth were similar in the 3 G6PD groups. However, G6PD-deficient and -intermediate infants had higher declines in hematocrit, bilirubin levels, and need for phototherapy than G6PD-normal infants (P < .001). CONCLUSIONS: The G6PD-deficient and G6PD-intermediate neonates had a higher risk of neonatal hyperbilirubinemia and would therefore need greater monitoring in the first week of life, even without exposure to known icterogenic agents.

Is it accurate to separate glucose-6-phosphate dehydrogenase activity in neonatal hyperbilirubinemia as deficient and normal?

BACKGROUND: The aim of this study was to investigate glucose 6-phosphate dehydrogenase (G6PD) activity in term and late preterm babies with severe neonatal hyperbilirubinemia and its relationship to the severity and treatment of this disorder, regardless of level of G6PD activity (deficient/normal). METHODS: A total of 529 term and late preterm (≥35 weeks) infants (228 female, 301 male) who were diagnosed with severe hyperbilirubinemia were included in this study. In each case, serum was collected to evaluate blood group, direct Coombs' test, complete blood cell count, total and direct bilirubin, thyroid-stimulating hormone, and G6PD activity. A partial correlation analysis was carried out to assess the relationship between G6PD activity and total bilirubin levels. RESULTS: A significant correlation was found between the severity of hyperbilirubinemia and G6PD activity in both males and females. Male neonates who had G6PD levels <12 U/g Hb required more phototherapy time than neonates who had G6PD levels ≥12 U/g Hb; and female neonates who had G6PD levels <16 U/g Hb required more phototherapy time than neonates who had G6PD levels ≥16 U/g Hb (p < 0.0001). When we analyzed only breastfed infants, a significant difference also emerged in both sexes. Decreased G6PD activity was associated with increased phototherapy time and the need for exchange transfusion. CONCLUSION: Routine checks of G6PD level in hyperbilirubinemic neonates are very important in providing proper medical management to prevent bilirubin-induced neurological dysfunction. Appropriate identification of G6PD (<12 U/g Hb for male infants and <16 U/g Hb for female infants) raises awareness of the severity of the condition and the necessity for immediate care of severe hyperbilirubinemic infants.

Should blood donors be routinely screened for glucose-6-phosphate dehydrogenase deficiency? A systematic review of clinical studies focusing on patients transfused with glucose-6-phosphate dehydrogenase-deficient red cells.

The risk factors associated with the use of glucose-6-phosphate dehydrogenase (G6PD)-deficient blood in transfusion have not yet been well established. Therefore, the aim of this review was to evaluate whether whole blood from healthy G6PD-deficient donors is safe to use for transfusion. The study undertook a systematic review of English articles indexed in COCHRANE, MEDLINE, EMBASE, and CINHAL, with no date restriction up to March 2013, as well as those included in articles' reference lists and those included in Google Scholar. Inclusion criteria required that studies be randomized controlled trials, case controls, case reports, or prospective clinical series. Data were extracted following the Preferred Reporting Items for Systematic Reviews using a previously piloted form, which included fields for study design, population under study, sample size, study results, limitations, conclusions, and recommendations. The initial search identified 663 potentially relevant articles, of which only 13 studies met the inclusion criteria. The reported effects of G6PD-deficient transfused blood on neonates and children appear to be more deleterious than effects reported on adult patients. In most cases, the rise of total serum bilirubin was abnormal in infants transfused with G6PD-deficient blood from 6 hours up to 60 hours after transfusion. All studies on neonates and children, except one, recommended a routine screening for G6PD deficiency for this at-risk subpopulation because their immature hepatic function potentially makes them less able to handle any excess bilirubin load. It is difficult to make firm clinical conclusions and recommendations given the equivocal results, the lack of standardized evaluation methods to categorize red blood cell units as G6PD deficient (some of which are questionable), and the limited methodological quality and low quality of evidence. Notwithstanding these limitations, based on our review of the available literature, there is little to suggest that G6PD-deficient individuals should be excluded from donating red blood cells, although transfusions of such blood may potentially have negative impacts on premature neonates or patients who need repeated transfusions, and thus, for this group, screening for G6PD deficiency may be appropriate.

Neonatal death suspected to be from sepsis was found to be kernicterus with G6PD deficiency.

We cared for a term male infant born to Burmese immigrants. At about 24 hours a total serum bilirubin (TSB) was 9.3 mg/dL, and phototherapy was begun. It was stopped 48 hours later, with a TSB of 10.9 mg/dL, and he was discharged from the hospital with an appointment for a repeat TSB check 48 hours later. A few hours before the appointment he became listless and apneic, and his parents took him to the emergency department of the regional children's hospital, where sepsis was suspected. The TSB was 41 mg/dL. He died 4 hours later, despite intensive care efforts, with opisthotonus and refractory hypotension. Blood drawn before the exchange transfusion had low glucose-6-phosphate dehydrogenase (G6PD) enzymatic activity, and sequencing of the G6PD gene revealed the G6PD Mahidol mutation (c.487G>A). Cultures and postmortem examination did not demonstrate an infectious process, but kernicterus was present. Acute kernicterus can mimic septic shock.

Nonimmune hydrops fetalis caused by G6PD deficiency hemolytic crisis and congenital dyserythropoietic anemia.

We present a case of a female neonate who had a nonimmune hydrops fetalis and severe hemolytic anemia due to a rare combination of glucose-6-phosphate dehydrogenase (G6PD) deficiency and congenital dyserythropoietic anemia. We conclude that in severe cases with persistent anemia one should search after delivery for a second reason other than G6PD deficiency alone.

Glucose-6-phosphate dehydrogenase deficiency in neonatal hyperbilirubinaemia: Hacettepe experience.

AIM: The aim of this study was to investigate the prevalence of glucose-6-phospate dehydrogenase (G6PD) deficiency in newborn infants with neonatal hyperbilirubinaemia and to compare the clinical features of G6PD-deficient and G6PD-normal newborn infants. METHODS: A total of 4906 term and preterm neonates with indirect hyperbilirubinaemia were retrospectively evaluated according to demographic, neonatal features, bilirubin levels, erythrocyte G6PD levels, other risk factors and treatments. RESULTS: Among 4906 newborn infants with indirect hyperbilirubinaemia, 55 (1.12%) neonates were G6PD-deficient. In our study, no statistically significant difference was detected between G6PD-deficient and G6PD-normal infants in relation to the time of onset of jaundice, bilirubin levels and duration of phototherapy. However, the incidence of exchange transfusion in G6PD-deficient infants was 16.4% while it was only 3.3% in G6PD normal infants (P < 0.05). CONCLUSION: Testing for G6PD must be ordered to all newborns who are receiving phototherapy and especially to those who are coming from the high incident geographical regions and less responsive to phototherapy.