Despite glucose-6-phosphate dehydrogenase (G6PD) deficiency prevalence of 5% in the Amazon, primaquine is administered without G6PD screening. This is an important cause of hospitalization among Plasmodium vivax–infected individuals, leading to life-threatening anemia and acute renal failure across endemic areas. In Manaus, the frequency of primaquine-induced hemolysis was 85.2 cases per 100 000 primaquine users.

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.

Background Acute kidney injury (AKI) is a common complication of Plasmodium falciparum malaria and can also occur secondary to P. malariae infections. Its association with P. vivax malaria is not well estimated neither understood.Methods Retrospective assessment of medical records was conducted among P. vivax malaria hospitalized patients in a reference hospital of Manaus, Brazilian Amazon, from 2009 to 2017. AKI was classified according to Acute Kidney Injury Network (AKIN) criteria and through the World Health Organization (WHO) criteria for severe malaria. Patients diagnosed with primaquine-induced hemolysis due to confirmed glucose 6-phosphate dehydrogenase deficiency (G6PDd) and chronic renal failure were excluded. Prevalence of AKI and factors associated to this complication were assessed.Results Out of 28,095 P. vivax malaria diagnoses during the study period in the reference center, 638 cases (2.3%) required hospitalization; with 433 (67.8%) of those patients having at least one creatinine measure. Twenty-two patients (5.1%) were diagnosed with AKI as per WHO criteria; 241 patients presented more than two creatinine measures, of which 117 (49.2%) patients had AKI per AKIN criteria. These were stratified in stage I (n=88; 75.2%), stage II (n=6; 5.1%), and stage III (n=23; 19.6%). Major risk factor for AKI was older age. Renal replacement therapy (dialysis) was necessary in 6 cases (1.4%).Conclusions AKI secondary to vivax malaria was not unfrequent amongst hospitalized patients and may be a potentially severe complication. WHO diagnostic criteria for malaria AKI was shown to underestimate the real burden of AKI. Renal impairment should be closely monitored especially in older patients.