Seven cases of probable endotoxin poisoning related to contaminated glutathione infusions

An isocratic HPLC-UV analytical procedure for assessment of glutathione and its related substances

Reduced glutathione (GSH) is an endogenous tripeptide antioxidant which plays a crucial role in a variety of physiological and pathological activities. Although GSH is not present in any FDA-approved drug product, GSH dietary supplement products and compounded GSH drugs are available to patients in the US. Several incidents of toxicity have occurred in recent years due to endotoxin or otherwise contaminated GSH in compounded drugs. Efficient and sensitive analytical methods are needed for assessing and ensuring the quality of GSH substance and associated drug or dietary supplement products. Impurities A (L-cysteinylglycine), B (cysteine), C (oxidized L-glutathione) and D (γ-L-glutamyl-L-cysteine) are the main related impurities for GSH drug substance which have been detected and quantified by capillary electrophoresis and qNMR analytical procedures. However, there are no reported HPLC methods for detecting or quantifying the three main related impurities A, B and D even though numerous HPLC analytical methods have been reported for analyzing GSH and impurity C. In this report, an isocratic HPLC-UV analytical procedure was developed and validated for separating and identifying GSH and related impurities A-D as well as a newly identified degradant, L-pyroglutamic acid (pGlu), within 10 minutes with resolution (RS) more than 3. The LOD and LOQ were determined to be 0.02 % w/w and 0.05 % w/w, respectively, for impurities A-D and pGlu. Importantly, the optimized HPLC analytical procedure for GSH assay does not have interference from impurities A, B and D, providing highly specific results compared to the commonly used iodine titration method. The newly validated analytical procedure was applied to assess different commercial GSH bulk substance samples. The results suggest that the analytical procedure described in this work is suitable for quality assessment of GSH samples.

Qualitative and quantitative analysis of glutathione and related impurities in pharmaceuticals by qNMR

In this study, an alternative method to compendial analytical procedures with enhanced detection and separation capabilities was validated for the quality assessment of glutathione (GSH) drug substance. The related impurities A, B, C, and D present in GSH drug substance were characterized using a one-dimension proton nuclear magnetic resonance (1D 1H NMR) method on a 600 MHz spectrometer equipped with a liquid nitrogen cryoprobe. Two sample preparations at different pH were optimized to ensure the unambiguous identification of different impurities in the GSH samples. Specifically, impurities A and C in a GSH sample can be tested at pH 3.0, while pH 7.4 is more suitable for testing impurities B and D. The quantitative NMR (qNMR) method was validated following International Council for Harmonisation (ICH) guidelines. The limit of detection (LOD) was less than 0.1% wt for an individual impurity, and the limit of quantitation (LOQ) ranged from 0.14 to 0.24% wt, using about 14 min experimental time per spectrum. Following validation, the qNMR method was applied to assess different commercial GSH bulk substance samples, an in-house compounded GSH drug product, and a GSH dietary supplement product. The method was also applied to monitor GSH degradation (hydrolysis and oxidation) over time to provide quantitative information on GSH degradation and stability. The results suggest that the qNMR method can serve as a highly specific and efficient orthogonal tool for assessing the quality of GSH pharmaceuticals, providing both qualitative and quantitative information on GSH and its related impurities A-D.

Diagnosis and treatment of "chronic Lyme": primum non nocere

BACKGROUND

Approximately 10% of patients experience prolonged symptoms after Lyme disease. PTLDS (post treatment Lyme disease syndrome) is a controversial topic. It has been described as a source of overdiagnosis and off-label treatment. This review aims to describe the diagnostic errors and adverse events associated with the diagnosis and treatment of PTLDS.

METHODS

systematic review of the literature in the Medline and Cochrane Library databases, according to PRISMA criteria, including randomized clinical trials (RCT), observational studies, and case reports addressing diagnostic errors and adverse events published between January 2010 and November 2020 in English or French. Selection used a quadruple reading process on the basis of the titles and abstracts of the different articles, followed by a full reading.

RESULTS

17 studies were included: 1 RCT, 6 observational studies and 10 case reports. In the 6 observational studies, overdiagnosis rates were very high, ranging from 80 to 100%. The new diagnoses were often psychiatric, rheumatological and neurological. Disorders with somatic symptoms were often cited. Diagnostic delays were identified for cancers and frontoparietal dementia. In the RCT and observational studies, prolonged anti-infective treatments were also responsible for adverse events, with emergency room visits and/or hospitalization. The most common adverse events were diarrhea, sometimes with Clostridium difficile colitis, electrolyte abnormalities, sepsis, bacterial and fungal infections, and anaphylactic reactions.

CONCLUSION

This review highlights the risks of prolonged anti-infective treatments that have not been proven to be beneficial in PTLDS. It emphasizes the ethical imperative of the "primum non nocere" principle, which underscores the importance of not causing harm to patients. Physicians should exercise caution in diagnosing PTLDS and consider the potential risks associated with off-label treatments.

Glucose-induced enhanced anti-oxidant activity inhibits apoptosis in goose fatty liver

The development of mammalian nonalcoholic fatty liver disease is associated with oxidative stress, reduced mitochondrial function, and increased apoptosis in hepatocytes; however, the expressions of mitochondria-related genes are elevated in goose fatty liver, suggesting that there may be a unique protective mechanism in goose fatty liver. The aim of the study was to investigate this protective mechanism in terms of anti-oxidant capacity. Our data showed no substantial differences in the mRNA expression levels of the apoptosis-related genes including B-cell lymphoma-2 (Bcl-2), BCL2-associated X (Bax), cysteinyl aspartate-specific proteinase-3 (Caspase-3), and cysteinyl aspartate-specific proteinase-9 (Caspase-9) in the livers of the control and overfeeding Lander geese groups. The protein expression levels of Caspase-3 and cleaved Caspase-9 were not markedly different between the groups. Compared with the control group, malondialdehyde content was significantly lower (P < 0.01), glutathione peroxidase (GSH-Px) activity, glutathione (GSH) content, and mitochondrial membrane potential levels were higher (P < 0.01) in the overfeeding group. The mRNA expression levels of the anti-oxidant genes superoxide dismutase 1 (SOD1), glutathione peroxidase 1 (GPX1), and glutathione peroxidase 2 (GPX2) were increased in goose primary hepatocytes after 40 mM and 60 mM glucose treatment. Reactive oxygen species (ROS) levels were significantly reduced (P < 0.01), whereas the mitochondrial membrane potential was maintained at normal levels. The mRNA expression levels of the apoptosis-related genes Bcl-2, Bax, and Caspase-3 were not substantial. There were no significant differences in the expression levels of Caspase-3 and cleaved Caspase-9 proteins. In conclusion, glucose-induced enhanced anti-oxidant capacity may help protect the function of mitochondria and inhibit the occurrence of apoptosis in goose fatty liver.