Genotypes and phenotypes of G6PD deficiency among Indonesian females across diagnostic thresholds of G6PD activity guiding safe primaquine therapy of latent malaria

Background Plasmodium vivax occurs as a latent infection of liver and a patent infection of red blood cells. Radical cure requires both blood schizontocidal and hypnozoitocidal chemotherapies. The hypnozoitocidal therapies available are primaquine and tafenoquine, 8-aminoquinoline drugs that can provoke threatening acute hemolytic anemia in patients having an X-linked G6PD-deficiency. Heterozygous females may screen as G6PD-normal prior to radical cure and go on to experience hemolytic crisis. Methods & findings This study examined G6PD phenotypes in 1928 female subjects living in malarious Sumba Island in eastern Indonesia to ascertain the prevalence of females vulnerable to diagnostic misclassification as G6PD-normal. All 367 (19%) females having <80% G6PD normal activity were genotyped. Among those, 103 (28%) were G6PD wild type, 251 (68·4%) were heterozygous, three (0·8%) were compound heterozygotes, and ten (2·7%) were homozygous deficient. The variants Vanua Lava, Viangchan, Coimbra, Chatham, and Kaiping occurred among them. Below the 70% of normal G6PD activity threshold, just 18 (8%) were G6PD-normal and 214 (92%) were G6PD-deficient. Among the 31 females with <30% G6PD normal activity were all ten homozygotes, all three compound heterozygotes, and just 18 were heterozygotes (7% of those). Conclusions In this population, most G6PD heterozygosity in females occurred between 30% and 70% of normal (69·3%; 183/264). The prevalence of females at risk of G6PD misclassification as normal by qualitative screening was 9·5% (183/1928). Qualitative G6PD screening prior to 8-aminoquinoline therapies against P. vivax may leave one in ten females at risk of hemolytic crisis, which may be remedied by point-of-care quantitative tests.

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Evaluating Percentage-Based Reporting of Glucose-6-Phosphate Dehydrogenase (G6PD) Enzymatic Activity in a National Reference Laboratory: Assessment of Patient Eligibility for Plasmodium vivax Radical Cure Therapy

American Journal of Clinical Pathology ◽

10.1093/ajcp/aqz116.005 ◽

2019 ◽

Vol 152 (Supplement_1) ◽

pp. S82-S82

Author(s):

Emilia Calvaresi ◽

Jonathan Genzen

Keyword(s):

Normal Activity ◽

Population Based ◽

G6pd Activity ◽

World Health ◽

Reference Laboratory ◽

Data Sets ◽

Radical Cure ◽

Laboratory Assessment ◽

Data Set ◽

Health Organization

Abstract Objectives The World Health Organization recommends measurement of G6PD activity prior to initiation of 8-aminoquinolones for the treatment of P vivax malaria. An estimated 400 million people worldwide have G6PD deficiency, making them susceptible to hemolysis under oxidative stress. A new single-dose therapy (radical cure) for malaria with tafenoquine is contraindicated in patients with <70% normal G6PD activity due to its prolonged circulating half-life. However, most clinical laboratories report G6PD activity in units g/Hb or units/1012 RBC and do not provide percentage of normal activity, making potential eligibility determination challenging. Methods Using an IRB-exempt protocol, a limited data set of consecutive G6PD quantitative results was retrieved from the clinical laboratory’s enterprise data warehouse. Laboratory testing of these specimens was previously performed at 37°C using an automated enzymatic assay (Pointe Scientific) configured on a cobas c501 chemistry analyzer (Roche Diagnostics). Data were assembled to include adults age 18 to 89 years and excluded repeat results from the same patients as well as outliers. Conclusion The final data set included 52,216 results (female, 55.9%, n = 29,173; male, 44.1%, n = 23,043) from 47 US states. An adjusted male median (100% G6PD activity) was derived using an approach proposed by the Bangkok Workshop guidelines (Domingo et al., Malaria Journal, 2013), modified to more accurately differentiate bimodal peaks in population G6PD histograms. The laboratory-specific, adjusted male median was 12.7 U g/Hb and was similar to peak values derived from alternative curve-fitting approaches. Applying this median to gender-specific data sets, 5.4% of males and 3.8% of females were found to have <70% of normal activity (<8.9 U g/Hb). This study demonstrates the feasibility of percentage-based G6PD result reporting in adults; further studies will query percentage-based reporting in pediatric populations. Population-based medians will vary based on G6PD assay type and temperature and should be established by laboratories prior to percentage-based reporting.

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PO 8609 PREVALENCE AND RISK FACTORS FOR GLUCOSE-6-PHOSPHATE DEHYDROGENASE (G6PD) DEFICIENCY IN TWO P. VIVAX MALARIA-ENDEMIC AREAS IN SUDAN

BMJ Global Health ◽

10.1136/bmjgh-2019-edc.164 ◽

2019 ◽

Vol 4 (Suppl 3) ◽

pp. A62.2-A62

Author(s):

Muzamil Mahdi Abdel Hamid ◽

Musab Albsheer ◽

Mohamed Muneer ◽

Lina Altinae ◽

Andrew A Lover

Keyword(s):

Risk Factors ◽

G6pd Deficiency ◽

Demographic Data ◽

Univariate Analysis ◽

G6pd Activity ◽

Radical Cure ◽

Major Health Problem ◽

Significant Difference ◽

Endemic Areas ◽

Glucose 6 Phosphate Dehydrogenase

BackgroundPlasmodium vivax malaria is a major health problem in Sudan and the parasite has become widely distributed in the recent years. The WHO recommends the use of primaquine as radical cure for liver dormant stage, the hypnozoite. However, prior its use, a test for Glucose-6-phosphate Dehydrogenase (G6PD) should be performed. The objective of the current study was to determine prevalence and risk factors for G6PD deficiency in two P. vivax malaria-endemic areas in Sudan.MethodsA cross-sectional study recruiting 557 subjects from two malaria-endemic areas in Sudan was conducted. Demographic data and blood samples were collected. G6PD activity was measured by spectrometry using SPINREACT enzymatic-UV kit.ResultsThe measured G6PD activities for both sites ranged from 0.6 to 37.7 U/g Hb, with a median value of 12.8 U/g Hb. There was a significant difference in enzyme activity by study site (p<0.001), but not by sex (p=0.91). Overall, across the two study sites, 22 (3.9%) is G6PDd (<30%). Prevalence of G6PDd (<30%) in Khartoum is 1.8% (4/230) compared to 4.8% (16/327) in New Hafla. In univariate analysis predictors of G6PDd were study site (odds ratio of G6PD activity <3.8, Khartoum relative to New Halfa=0.22 (95% CI: 0.08 to 0.66), p=0.006), and recent antibiotic use (OR=2.45 (95% CI: 1.1 to 5.5), p=0.027). In multivariate analysis, the only factor that was significant was the individual’s weight in kilograms, with an OR of 0.97 (95% CI 0.95 to 0.99, p=0.014).ConclusionG6PD deficiency is less prevalent among Sudanese population and this indicates that the use of primaquine for radical cure of P. vivax malaria is safe.

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Optimizing G6PD testing for Plasmodium vivax case management: why sex, counseling, and community engagement matter

Wellcome Open Research ◽

10.12688/wellcomeopenres.15700.1 ◽

2020 ◽

Vol 5 ◽

pp. 21

Author(s):

Cindy S Chu ◽

Germana Bancone ◽

Maureen Kelley ◽

Nicole Advani ◽

Gonzalo J Domingo ◽

...

Keyword(s):

Plasmodium Vivax ◽

G6pd Deficiency ◽

Point Of Care ◽

Genetic Disorder ◽

Treatment Options ◽

Radical Cure ◽

Sex Counseling ◽

Point Of Care Diagnostics ◽

Genetic Test Results ◽

Human Genetic Disorder

Safe access to the most effective treatment options for Plasmodium vivax malaria are limited by the absence of accurate point-of-care testing to detect glucose-6-phosphate dehydrogenase (G6PD) deficiency, the most common human genetic disorder. G6PD-deficient patients are at risk of life-threatening hemolysis when exposed to 8-aminoquinolines, the only class of drugs efficacious against P. vivax hypnozoites. Until recently, only qualitative tests were available in most settings. These accurately identify patients with severe G6PD deficiency (mostly male) but not patients with intermediate G6PD deficiency (always female). This has led to and reinforced a gap in awareness in clinical practice of the risks and implications of G6PD deficiency in females—who, unlike males, can have a heterozygous genotype for G6PD. Increasing recognition of the need for radical cure of P. vivax, first for patients’ health and then for malaria elimination, is driving the development of new point-of-care tests for G6PD deficiency and their accessibility to populations in low-resource settings. The availability of simple, affordable, and accurate point-of-care diagnostics for the precise classification of the three G6PD phenotypes can reduce sex-linked disparities by ensuring safe and effective malaria treatment, providing opportunities to develop supportive counseling to enhance understanding of genetic test results, and improving the detection of all G6PD deficiency phenotypes in newborns and their family members.

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Real-life implementation of a G6PD deficiency screening qualitative test into routine vivax malaria diagnostic units in the Brazilian Amazon (SAFEPRIM study)

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0009415 ◽

2021 ◽

Vol 15 (5) ◽

pp. e0009415

Author(s):

Jose Diego Brito-Sousa ◽

Felipe Murta ◽

Sheila Vitor-Silva ◽

Vanderson S. Sampaio ◽

Maxwell O. Mendes ◽

...

Keyword(s):

Health Care Professionals ◽

G6pd Deficiency ◽

Endemic Area ◽

Point Of Care ◽

Training Session ◽

Real Life ◽

High Sensitivity ◽

Brazilian Amazon ◽

Radical Cure ◽

Effectiveness Of Training

Background Glucose-6-phosphate dehydrogenase (G6PD) deficiency greatly hinders Plasmodium vivax malaria radical cure and further elimination due to 8-aminoquinolines-associated hemolysis. Although the deleterious health effects of primaquine in G6PD deficient individuals have been known for over 50 years, G6PD testing is not routinely performed before primaquine treatment in most P. vivax endemic areas. Method/Principal findings The qualitative CareStart G6PD screening test was implemented in 12 malaria treatment units (MTUs) in the municipality of Rio Preto da Eva, Western Brazilian Amazon, a malaria endemic area, between February 2019 and early January 2020. Training materials were developed and validated; evaluations were conducted on the effectiveness of training health care professionals (HCPs) to perform the test, the interpretation and reliability of routine testing performed by HCPs, and perceptions of HCPs and patients. Most HCPs were unaware of G6PD deficiency and primaquine-related adverse effects. Most of 110 HCPs trained (86/110, 78%) were able to correctly perform the G6PD test after a single 4-hour training session. The test performed by HCPs during implementation showed 100.0% (4/4) sensitivity and 68.1% (62/91) specificity in identifying G6PD deficient patients as compared to a point-of-care quantitative test (Standard G6PD). Conclusions/Significance G6PD screening using the qualitative CareStart G6PD test performed by HCPs in MTUs of an endemic area showed high sensitivity and concerning low specificity. The amount of false G6PD deficiency detected led to substantial loss of opportunities for radical cure.

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Optimizing G6PD testing for Plasmodium vivax case management and beyond: why sex, counseling, and community engagement matter

Wellcome Open Research ◽

10.12688/wellcomeopenres.15700.2 ◽

2020 ◽

Vol 5 ◽

pp. 21

Author(s):

Cindy S Chu ◽

Germana Bancone ◽

Maureen Kelley ◽

Nicole Advani ◽

Gonzalo J Domingo ◽

...

Keyword(s):

Plasmodium Vivax ◽

G6pd Deficiency ◽

Point Of Care ◽

Genetic Disorder ◽

Treatment Options ◽

Radical Cure ◽

Sex Counseling ◽

Point Of Care Diagnostics ◽

Genetic Test Results ◽

Human Genetic Disorder

Safe access to the most effective treatment options for Plasmodium vivax malaria are limited by the absence of accurate point-of-care testing to detect glucose-6-phosphate dehydrogenase (G6PD) deficiency, the most common human genetic disorder. G6PD-deficient patients are at risk of life-threatening hemolysis when exposed to 8-aminoquinolines, the only class of drugs efficacious against P. vivax hypnozoites. Until recently, only qualitative tests were available in most settings. These can identify patients with severe G6PD deficiency (mostly male) but not patients with intermediate G6PD deficiency (always female). This has led to and reinforced a gap in awareness in clinical practice of the risks and implications of G6PD deficiency in females—who, unlike males, can have a heterozygous genotype for G6PD. Increasing recognition of the need for radical cure of P. vivax, first for patients’ health and then for malaria elimination, is driving the development of new point-of-care tests for G6PD deficiency and their accessibility to populations in low-resource settings. The availability of user-friendly, affordable, and accurate quantitative point-of-care diagnostics for the precise classification of the three G6PD phenotypes can reduce sex-linked disparities by ensuring safe and effective malaria treatment, providing opportunities to develop supportive counseling to enhance understanding of genetic test results, and improving the detection of all G6PD deficiency phenotypes in newborns and their family members.

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Reference and point-of-care testing for G6PD deficiency: Blood disorder interference, contrived specimens, and fingerstick equivalence and precision

PLoS ONE ◽

10.1371/journal.pone.0257560 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0257560

Author(s):

Sampa Pal ◽

Jane Myburgh ◽

Pooja Bansil ◽

Amanda Hann ◽

Lynn Robertson ◽

...

Keyword(s):

Test Performance ◽

G6pd Deficiency ◽

Clinical Performance ◽

Point Of Care ◽

The United States ◽

G6pd Activity ◽

Good Precision ◽

Point Of Care Testing ◽

Blood Disorders ◽

Blood Disorder

Certain clinical indications and treatments such as the use of rasburicase in cancer therapy and 8-aminoquinolines for Plasmodium vivax malaria treatment would benefit from a point-of-care test for glucose-6-phosphate dehydrogenase (G6PD) deficiency. Three studies were conducted to evaluate the performance of one such test: the STANDARD™ G6PD Test (SD BIOSENSOR, South Korea). First, biological interference on the test performance was evaluated in specimens with common blood disorders, including high white blood cell (WBC) counts. Second, the test precision on fingerstick specimens was evaluated against five individuals of each, deficient, intermediate, and normal G6PD activity status. Third, clinical performance of the test was evaluated at three point-of-care settings in the United States. The test performed equivalently to the reference assay in specimens with common blood disorders. High WBC count blood samples resulted in overestimation of G6PD activity in both the reference assay and the STANDARD G6PD Test. The STANDARD G6PD Test showed good precision on multiple fingerstick specimens from the same individual. The same G6PD threshold values (U/g Hb) were applied for a semiquantitative interpretation for fingerstick- and venous-derived results. The sensitivity/specificity values (95% confidence intervals) for the test for G6PD deficiency were 100 (92.3–100.0)/97 (95.2–98.2) and 100 (95.7–100.0)/97.4 (95.7–98.5) for venous and capillary specimens, respectively. The same values for females with intermediate (> 30% to ≤ 70%) G6PD activity were 94.1 (71.3–99.9)/88.2 (83.9–91.7) and 82.4 (56.6–96.2)/87.6(83.3–91.2) for venous and capillary specimens, respectively. The STANDARD G6PD Test enables point-of-care testing for G6PD deficiency.

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THE INFLUENCE OF HAEMOGLOBIN-S AND G6PD DEFICIENCY ON THE ACTIVITY OF THE 17β-HYDROXYSTEROID DEHYDROGENASE OF INTACT HUMAN ERYTHROCYTES

Acta Endocrinologica ◽

10.1530/acta.0.0750793 ◽

1974 ◽

Vol 75 (4) ◽

pp. 793-800

Author(s):

A. O. Sogbesan ◽

O. A. Dada ◽

B. Kwaku Adadevoh

Keyword(s):

Enzyme Activity ◽

Dehydrogenase Activity ◽

Sex Steroids ◽

G6pd Deficiency ◽

Incubation Medium ◽

Hydroxysteroid Dehydrogenase ◽

G6pd Activity ◽

Reverse Transformation ◽

Oxidative Transformation ◽

Haemoglobin S

ABSTRACT The 17β-hydroxysteroid dehydrogenase activity in intact erythrocytes of Nigerian patients, in particular with regard to haemoglobin genotypes and G6PD* activity was studied. The G6PD activity of the erythrocyte did not affect the oxidative transformation of testosterone to androstenedione and of oestradiol to oestrone. The reduction (reverse transformation) was inhibited in G6PD-deficient erythrocytes but this inhibition was offset by the addition of 0.025 m glucose to the incubation medium. The per cent oxidation transformation of testosterone was higher in Hb-AA than in Hb-SS erythrocytes. It is suggested that the differences may be a result of either lower enzyme activity in the Hb-SS erythrocytes or of differences in the uptake and possibly binding of sex steroids by intact Hb-SS and Hb-AA erythrocytes.

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Longitudinal remotely mentored self-performed lung ultrasound surveillance of paucisymptomatic Covid-19 patients at risk of disease progression

The Ultrasound Journal ◽

10.1186/s13089-021-00231-9 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Andrew W. Kirkpatrick ◽

Jessica L. McKee ◽

John M. Conly

Keyword(s):

At Risk ◽

Lung Ultrasound ◽

Point Of Care ◽

Human Life ◽

Vital Signs ◽

Home Monitoring ◽

Cost Effective ◽

Care Providers ◽

Vital Signs Monitoring ◽

Ultrasound Probes

AbstractCOVID-19 has impacted human life globally and threatens to overwhelm health-care resources. Infection rates are rapidly rising almost everywhere, and new approaches are required to both prevent transmission, but to also monitor and rescue infected and at-risk patients from severe complications. Point-of-care lung ultrasound has received intense attention as a cost-effective technology that can aid early diagnosis, triage, and longitudinal follow-up of lung health. Detecting pleural abnormalities in previously healthy lungs reveal the beginning of lung inflammation eventually requiring mechanical ventilation with sensitivities superior to chest radiographs or oxygen saturation monitoring. Using a paradigm first developed for space-medicine known as Remotely Telementored Self-Performed Ultrasound (RTSPUS), motivated patients with portable smartphone support ultrasound probes can be guided completely remotely by a remote lung imaging expert to longitudinally follow the health of their own lungs. Ultrasound probes can be couriered or even delivered by drone and can be easily sterilized or dedicated to one or a commonly exposed cohort of individuals. Using medical outreach supported by remote vital signs monitoring and lung ultrasound health surveillance would allow clinicians to follow and virtually lay hands upon many at-risk paucisymptomatic patients. Our initial experiences with such patients are presented, and we believe present a paradigm for an evolution in rich home-monitoring of the many patients expected to become infected and who threaten to overwhelm resources if they must all be assessed in person by at-risk care providers.

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G6PD deficiency among malaria-infected national groups at the western part of Myanmar with implications for primaquine use in malaria elimination

Tropical Medicine and Health ◽

10.1186/s41182-021-00339-7 ◽

2021 ◽

Vol 49 (1) ◽

Author(s):

Kay Thwe Han ◽

Zay Yar Han ◽

Kyin Hla Aye ◽

Khin Thet Wai ◽

Aung Thi ◽

...

Keyword(s):

Enzyme Activity ◽

Malaria Elimination ◽

G6pd Deficiency ◽

Control Program ◽

Cross Sectional Study ◽

Diagnostic Tools ◽

Asymptomatic Malaria ◽

Radical Cure ◽

Readiness Assessment ◽

Cross Sectional

Abstract Background Glucose 6-phosphate dehydrogenase deficiency (G6PDd) plays a central role in readiness assessment for malaria elimination in Myanmar by 2030 that includes primaquine (PQ) use. The risk of hemolysis in G6PDd individuals hampers the widespread use of primaquine safely in malaria-infected patients. In the pre-elimination era, it is important to screen initially for asymptomatic malaria in combination with G6PD deficiency by applying more sensitive diagnostic tools. Therefore, this study examined the proportion of G6PDd and the distribution of G6PD genotypes among malaria-infected national groups in Myanmar before initiation of malaria elimination strategies. Methods A cross-sectional study in one township each with high malaria burden from two states in the western part of Myanmar, was conducted during 2016-2018, and 320 participants (164 Rakhine and 156 Chin National groups) were recruited. We used RDT and ultrasensitive polymerase chain reaction (us PCR) method to confirm malaria infection, and a G6PD RDT(CareStart) to detect G6PDd and PCR/restriction fragment length polymorphism (RFLP) method to confirm the variant of G6PDd for genotyping. G6PD enzyme activity was measured by G6PD Biosensor (CareStart). Results Malaria positivity rates detected by RDT were lower than those detected by us PCR in the combined samples [13% (42/320) vs. 21% (67/320)] as well as in the Rakhine samples [17% (28/164) vs. 25% (41/164)] and in Chin samples [9% (14/156) vs. 17% (26/156)]. G6PD deficiency rates were approximately 10% in both the combined samples and specific national groups. For G6PD enzyme activity in the combined samples, G6PDd (defined as < 30% of adjusted male median) was 10% (31/320) and severe G6PDd (< 10% of AMM) was 3% (9/320). Among malaria-infected patients with positive by both RDT and usPCR, G6PDd was less than 20% in each national group. G6PD genotyping showed that the G6PD Mahidol (G487A) was the major variant. Conclusions The varying degree of G6PDd detected among malaria-infected national groups by advanced diagnostic tools, strongly support the recommend G6PD testing by the National Malaria Control Program and the subsequent safe treatment of P. vivax by primaquine for radical cure. Establishing a field monitoring system to achieve timely malaria elimination is mandatory to observe the safety of patients after PQ treatment.

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460. Point-of-Care, In-Home SARS-CoV-2 IgG Antibody Testing to Assess Seroprevalence in At-Risk Health Care Workers

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa439.653 ◽

2020 ◽

Vol 7 (Supplement_1) ◽

pp. S297-S297

Author(s):

Eric G Meissner ◽

Christine Litwin ◽

Tricia Crocker ◽

Elizabeth Mack ◽

Lauren Card

Keyword(s):

Health Care ◽

At Risk ◽

Health Care Workers ◽

Medical Center ◽

Point Of Care ◽

Academic Medical Center ◽

Significant Risk ◽

Documented Infection ◽

Inconclusive Result ◽

Care Workers

Abstract Background Health care workers are at significant risk for infection with the novel coronavirus SARS-CoV-2. Methods We utilized a point-of-care, lateral flow SARS-CoV-2 IgG immunoassay (RayBiotech) to conduct a seroprevalence study in a cohort of at-risk health care workers (n=339) and normal-risk controls (n=100) employed at an academic medical center. To minimize exposure risk while conducting the study, consents were performed electronically, tests were mailed and then self-administered at home using finger stick blood, and subjects uploaded a picture of the test result while answering an electronic questionnaire. We also validated the assay using de-identified serum samples from patients with PCR-proven SARS-CoV-2 infection. Results Between April 14th and May 6th 2020, 439 subjects were enrolled. Subjects were 68% female, 93% white, and most were physicians (38%) and nurses (27%). In addition, 37% had at least 1 respiratory symptom in the prior month, 34% had cared for a patient with known SARS-CoV-2 infection, 57% and 23% were worried about exposure at work or in the community, respectively, and 5 reported prior documented SARS-CoV-2 infection. On initial testing, 3 subjects had a positive IgG test, 336 had a negative test, and 87 had an inconclusive result. Of those with an inconclusive result who conducted a repeat test (85%), 96% had a negative result. All 3 positive IgG tests were in subjects reporting prior documented infection. Laboratory validation showed that of those with PCR-proven infection more than 13 days prior, 23/30 were IgG positive (76% sensitivity), whereas 1/26 with a negative prior PCR test were seropositive (95% specificity). Repeat longitudinal serologic testing every 30 days for up to 4 times is currently in progress. Conclusion We conducted a contact-free study in the setting of a pandemic to assess SARS-CoV-2 seroprevalence in an at-risk group of health care workers. The only subjects found to be IgG positive were those with prior documented infection, even though a substantial proportion of subjects reported significant potential occupational or community exposure and symptoms that were potentially compatible with SARS-COV-2 infection. Disclosures All Authors: No reported disclosures

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