Chronic haemolytic anaemia and glucose-6 phosphate dehydrogenase deficiency. Case report and review of the literature

The Role of Methemoglobin and Carboxyhemoglobin in COVID-19: A Review

Following the outbreak of a novel coronavirus (SARS-CoV-2) associated with pneumonia in China (Corona Virus Disease 2019, COVID-19) at the end of 2019, the world is currently facing a global pandemic of infections with SARS-CoV-2 and cases of COVID-19. Since severely ill patients often show elevated methemoglobin (MetHb) and carboxyhemoglobin (COHb) concentrations in their blood as a marker of disease severity, we aimed to summarize the currently available published study results (case reports and cross-sectional studies) on MetHb and COHb concentrations in the blood of COVID-19 patients. To this end, a systematic literature research was performed. For the case of MetHb, seven publications were identified (five case reports and two cross-sectional studies), and for the case of COHb, three studies were found (two cross-sectional studies and one case report). The findings reported in the publications show that an increase in MetHb and COHb can happen in COVID-19 patients, especially in critically ill ones, and that MetHb and COHb can increase to dangerously high levels during the course of the disease in some patients. The medications given to the patient and the patient’s glucose-6-phospate dehydrogenase (G6PD) status seem to be important factors determining the severity of the methemoglobinemia and carboxyhemoglobinemia. Therefore, G6PD status should be determined before medications such as hydroxychloroquine are administered. In conclusion, MetHb and COHb can be elevated in COVID-19 patients and should be checked routinely in order to provide adequate medical treatment as well as to avoid misinterpretation of fingertip pulse oximetry readings, which can be inaccurate and unreliable in case of elevated MetHb and COHb levels in the blood.

Molecular Profile of Priapism Associated with Low Nitric Oxide Bioavailability

Priapism is a disorder in which prolonged penile erection persists uncontrollably, potentially leading to tissue damage. Priapism commonly afflicts patient populations with severely low nitric oxide (NO) bioavailability. Because NO is a primary mediator of erection, the molecular mechanisms involved in priapism pathophysiology associated with low NO bioavailability are not well-understood. The objective of this study was to identify dysregulated molecular targets and signaling pathways in penile tissue of a mouse model of low NO bioavailability that have potential relevance to priapism. Neuronal plus endothelial NO synthase double knockout mice (NOS1/3^-/-) were used as a model of low NO bioavailability. Priapic-like activity was demonstrated in the NOS1/3^-/- mice relative to wild-type (WT) mice by the measurement of prolonged erections following cessation of electrical stimulation of the cavernous nerve. Penile tissue was processed and analyzed by reverse-phase liquid chromatography tandem mass spectrometry. As a result, 1279 total proteins were identified and quantified by spectral counting, 46 of which were down-regulated and 110 of which were up-regulated in NOS1/3^-/- versus WT (P < 0.05). Ingenuity Pathway Analysis of differentially expressed proteins revealed increased protein kinase A and G-protein coupled receptor signaling in NOS1/3^-/- penises, which represent potential mechanisms contributing to priapism for secondary to low NO bioavailability.

Comparison of Three Screening Test Kits for G6PD Enzyme Deficiency: Implications for Its Use in the Radical Cure of Vivax Malaria in Remote and Resource-Poor Areas in the Philippines

Objective

We evaluated a battery of Glucose-6-Phosphate Dehydrogenase diagnostic point-of-care tests (PoC) to assess the most suitable product in terms of performance and operational characteristics for remote areas.

Methods

Samples were collected in Puerto Princesa City, Palawan, Philippines and tested for G6PD deficiency with a fluorescent spot test (FST; Procedure 203, Trinity Biotech, Ireland), the semiquantitative WST8/1-methoxy PMS (WST; Dojindo, Japan) and the Carestart G6PD Rapid Diagnostic Test (CSG; AccessBio, USA). Results were compared to spectrophotometry (Procedure 345, Trinity Biotech, Ireland). Sensitivity and specificity were calculated for each test with cut-off activities of 10%, 20%, 30% and 60% of the adjusted male median.

Results

The adjusted male median was 270.5 IU/10¹² RBC. FST and WST were tested on 621 capillary blood samples, the CSG was tested on venous and capillary blood on 302 samples. At 30% G6PD activity, sensitivity for the FST was between 87.7% (95%CI: 76.8% to 93.9%) and 96.5% (95%CI: 87.9% to 99.5%) depending on definition of intermediate results; the WST was 84.2% (95%CI: 72.1% to 92.5%); and the CSG was between 68.8% (95%CI: 41.3% to 89.0%) and 93.8% (95%CI: 69.8% to 99.8%) when the test was performed on capillary or venous blood respectively. Sensitivity of FST and CSG (tested with venous blood) were comparable (p>0.05). The analysis of venous blood samples by the CSG yielded significantly higher results than FST and CSG performed on capillary blood (p<0.05). Sensitivity of the CSG varied depending on source of blood used (p<0.05).

Conclusion

The operational characteristics of the CSG were superior to all other test formats. Performance and operational characteristics of the CSG performed on venous blood suggest the test to be a good alternative to the FST.

Splenic artery pseudoaneurysm due to seatbelt injury in a glucose-6-phosphate dehydrogenase-deficient adult

A 23-year-old man presented with abdominal pain after suffering blunt trauma caused by a seatbelt injury. His low platelet count of 137 × 10(9)/L was initially attributed to trauma and his underlying hypersplenism due to glucose-6-phosphate dehydrogenase (G6PD) deficiency. Despite conservative management, his platelet count remained persistently reduced even after his haemoglobin and clotting abnormalities were stabilised. After a week, follow-up imaging revealed an incidental finding of a pseudoaneurysm (measuring 9 mm × 8 mm × 10 mm) adjacent to a splenic laceration. The pseudoaneurysm was successfully closed via transcatheter glue embolisation; 20% of the spleen was also embolised. A week later, the platelet count normalised, and the patient was subsequently discharged. This case highlights the pitfalls in the detection of a delayed occurrence of splenic artery pseudoaneurysm after blunt injury via routine delayed phase computed tomography. While splenomegaly in G6PD may be a predisposing factor for injury, a low platelet count should arouse suspicion of internal haemorrhage rather than hypersplenism.

Glucose-6-phosphate dehydrogenase deficiency and idiopathic presenile cataract in Dalmatia, Croatia

BACKGROUND

Impaired activity of the enzyme glucose-6-phosphate dehydrogenase (G6PD) has been suggested as a risk factor in cataractogenesis. The aim of this study was to determine the G6PD activity level in 89 male subjects of Dalmatian origin with idiopathic presenile cataracts.

METHODS

G6PD activity was determined by a quantitative spectrophotometric method.

RESULTS

Of 89 males with presenile cataracts only one (1.1%) had G6PD deficiency. The G6PD deficiency prevalence rate among males with presenile cataracts is not significantly different (p > 0.05) from the prevalence of G6PD deficiency in the general population of Dalmatia (0.75% among men).

INTERPRETATION

The results of this study suggest that G6PD deficiency does not represent a pathogenetic factor in presenile cataract, at least not in the population of the southern part of Croatia.

Anästhesie bei Patienten mit Glukose-6-Phosphat-Dehydrogenase-Mangel

Glucose-6-phosphate dehydrogenase (G6PD) deficiency, a frequent congenital human enzyme defect, is the most frequent cause of hemolytic anemia triggered by drugs or infectious diseases. Drugs which induce acute hemolysis in patients with G6PD deficiency are often used in anesthesia and perioperative pain therapy. Considering the fact that patients from geographic regions with a high prevalence of the disease are often treated in European hospitals, special attention should be paid to this problem. We report a case of a 30-year-old female patient with favism and review the disease and anesthesia-related implications.

Laparoscopic splenectomy: present status and future perspective

Laparoscopic splenectomy has become widely accepted as the approach of choice for the surgical treatment of benign and malignant hematologic diseases. Advances in technology have led to better outcomes for the procedure, and have allowed surgeons to apply the technique to disease processes that were at one time felt to be contraindications to laparoscopic splenectomy. However, challenges still remain. There is a steep learning curve associated with the procedure. The development of cost-effective laparoscopic simulators to target the skills required for laparoscopic splenectomy and other laparoscopic procedures is essential. The advent of devices which isolate and seal the large blood vessels that surround the spleen have reduced intra-operative bleeding and minimized conversions to open splenectomy. Improvements in optics and instrumentation, as well as robotic technology, will continue to define the frontier of minimally invasive surgery, and further facilitate the acceptance of laparoscopic splenectomy for the treatment of benign and malignant hematologic diseases.