Acquired 5-oxoproline acidemia successfully treated with N-acetylcysteine

Pyroglutamic acidosis in the setting of Staphylococcus aureus bacteremia treated with flucloxacillin-An uncommon cause of high anion gap metabolic acidosis

Pyroglutamic acidosis (PGA) or 5-Oxoprolinuria is an uncommon and often overlooked cause of high anion gap metabolic acidosis (HAGMA). This case highlights the importance of systematically approaching HAGMA, and to consider PGA as a differential diagnosis when medications that disrupt the γ-glutamyl cycle such as flucloxacillin and paracetamol are present.

Severe acidosis due to 5-oxoprolinase inhibition by flucloxacillin in a patient with shoulder prosthesis joint infection

Abstract. We report a case of a 64-year-old female patient with severe metabolic acidosis. Inhibition of 5-oxoprolinase by flucloxacillin was found to be the cause of the metabolic derailment.

Severe Anion Gap Metabolic Acidosis Resulting from Combined Chronic Acetaminophen Toxicity and Starvation Ketosis: A Case Report and Literature Review

Patient: Male, 68-year-old

Final Diagnosis: 5-oxoproline toxicity • anion gap metabolic acidosis • starvation ketoacidosis

Symptoms: Confusion • weakness

Medication: —

Clinical Procedure: —

Specialty: General and Internal Medicine • Nephrology

Malnourishment-Associated Acetaminophen Toxicity in Pregnancy

BACKGROUND

Although acetaminophen is commonly used in pregnancy, it can deplete glutathione concentrations and cause accumulation of 5-oxoproline, with subsequent metabolic acidosis.

CASE

A malnourished 25-year-old woman, G2P1001, with chronic acetaminophen use presented with abdominal pain and high anion gap metabolic acidosis. After ruling out other potential causes, her urine 5-oxoproline level was found to be elevated. She received N-acetylcysteine, with resolution of the acidosis.

CONCLUSION

Those who care for pregnant patients should remain alert to 5-oxoprolinemia as a cause of metabolic acidosis during pregnancy. Care must be taken when using acetaminophen in states of malnutrition. N-acetylcysteine seems to be an effective antidote.

Flucloxacillin and paracetamol induced pyroglutamic acidosis

A 75-year-old woman was admitted to a regional hospital with an acute kidney injury (AKI) and nausea on a background of recent treatment for Staphylococcus aureus bacteraemia secondary to pneumonia. The treatment thereof resulted in a high anion gap metabolic acidosis (HAGMA). The pneumonia was initially treated with intravenous piperacillin and tazobactam and the patient transferred to a tertiary hospital. There, the diagnosis of S. aureus bacteraemia secondary to a pulmonary source was confirmed and treatment was changed to intravenous flucloxacillin and the patient was discharged to hospital in the home (HITH is a service that allows short-term healthcare at home to be provided to people who would otherwise need to be in hospital) to complete the antibiotic course. Five weeks after commencing flucloxacillin, the patient was referred back to hospital with nausea and worsening kidney function with an associated significant HAGMA. The patient has a background of chronic kidney disease and chronic back pain for which she was taking long-term paracetamol. The HAGMA was determined to be due to a pyroglutamic acidosis (PGA), deemed secondary to the combined use of paracetamol and flucloxacillin. This was subsequently confirmed with a plasma pyroglutamic acid concentration level of 7467 µmol/L (reference range 20-50 µmol/L) and a urinary level of 1700 mmol/mol creatinine (<110 mmol/mol creatinine). To our knowledge, this is the highest plasma and urinary levels published to date. Furthermore, considering the common use of paracetamol and penicillins, it is important to recognise HAGMA as a potential complication of co-administration of paracetamol and iso-oxylopenicillin. The HAGMA resolved after cessation of flucloxacillin despite the continuation of paracetamol and without administration of N-acetylcysteine. PGA-related HAGMA appears to be a unique potential side effect of iso-oxylopenicillin rather than other beta-lactams.

Lesson of the month 1: A rare adverse reaction between flucloxacillin and paracetamol

Flucloxacillin, a beta-lactam antibiotic, is a commonly prescribed antibiotic for the treatment of infections caused by staphylococci and streptococci, most notably Staphylococcus aureus Paracetamol is one of the most dispensed medications by NHS England and is used for the treatment of fever and pain.1 However most doctors are unaware that concurrent use of these drugs can cause a potentially fatal drug interaction due to pyroglutamic acidosis (PGA), also known as 5-oxoprolinaemia. PGA is a rare cause of raised anion gap metabolic acidosis due to disruption of the γ-glutamyl cycle. We report the case of a patient with multiple comorbidities who developed PGA due to coadministration of paracetamol and flucloxacillin.

Discriminating high-risk cervical Human Papilloma Virus infections with urinary biomarkers via non-targeted GC-MS-based metabolomics

Genital human papillomavirus (HPV) is the world’s most commonly diagnosed sexually transmitted infection, and high-risk HPV types are strongly linked to cervical dysplasia and carcinoma. Puerto Ricans are among the US citizens with higher HPV prevalence and lower screening rates and access to treatment. This bleak statistic was as a motivation to detect biomarkers for early diagnosis of HPV in this population. We collected both urine and cervical swabs from 43 patients attending San Juan Clinics. Cervical swabs were used for genomic DNA extractions and HPV genotyping with the HPV SPF10-LiPA25 kit, and gas chromatography-mass spectrometry (GC-MS) was employed on the urine-derived products for metabolomics analyses. We aimed at discriminating between patients with different HPV categories: HPV negative (HPV-), HPV positive with simultaneous low and high-risk infections (HPV+B) and HPV positive exclusively high-risk (HPV+H). We found that the metabolome of HPV+B is closer to HPV- than to HPV+H supporting evidence that suggests HPV co-infections may be antagonistic due to viral interference leading to a lower propensity for cervical cancer development. In contrast, metabolites of patients with HPV+H were significantly different from those that were HPV-. We identified three urinary metabolites 5-Oxoprolinate, Erythronic acid and N-Acetylaspartic acid that discriminate HPV+H cases from negative controls. These metabolites are known to be involved in a variety of biochemical processes related to energy and metabolism and may likely be biomarkers for HPV high-risk cervical infection. However, further validation should follow using a larger patient cohort and diverse populations to confirm our finding.