Nitrous Oxide Abuse: Clinical Outcomes, Pharmacology, Pharmacokinetics, Toxicity and Impact on Metabolism.

The recreational use of nitrous oxide (N2O), also called laughing gas, has increased significantly in recent years. In 2022, the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) recognized it as one of the most prevalent psychoactive substances used in Europe. Chronic nitrous oxide (N2O) exposure can lead to various clinical manifestations. The most frequent symptoms are neurological (sensitive or motor disorders), but there are also other manifestations like psychiatric manifestations or cardiovascular disorders (thrombosis events). N2O also affects various neurotransmitter systems, leading to its anesthetic, analgesic, anxiolytic and antidepressant properties. N2O is very challenging to measure in biological matrices. Thus, in cases of N2O intoxication, indirect biomarkers such as vitamin B12, plasma homocysteine and plasma MMA should be explored for diagnosis and assessment. Others markers, like oxidative stress markers, could be promising but need to be further investigated.

Spontaneous remission of pendulum swinging thyroid disease in Down syndrome.

Summary: Rare patients who have both thyroid-stimulating hormone (TSH) receptor-stimulating and -blocking antibodies can develop 'pendulum swinging' thyroid dysfunction. A 9-year-old girl with Down syndrome was treated with carbimazole for Graves' disease. After 2 years of treatment, she became profoundly biochemically hypothyroid, and this persisted after carbimazole was discontinued. Low-dose L-thyroxine was commenced. This was subsequently also discontinued as biochemical hyperthyroidism developed. TSH receptor antibody bioassay identified both TSH receptor-stimulating and -blocking antibodies. Mild hyperthyroidism persisted and while consultations regarding definitive treatment were ongoing, medication was not recommenced. Thyroid function normalised spontaneously and she has remained euthyroid for the past 3 years. Previous reports have advised definitive treatment; however, our patient developed spontaneous remission which has been prolonged and definitive therapies have been avoided. It is not yet known how commonly this particular phenomenon occurs. Learning points: Rare patients who have both TSH receptor-stimulating and -blocking antibodies can switch between hyperthyroidism and hypothyroidism or vice versa during treatment with antithyroid drugs or thyroxine. Metamorphic thyroid autoimmunity is more common in Down syndrome. Switching between hyperthyroidism and hypothyroidism and back again is less commonly reported. Definitive treatment such as radioactive iodine or thyroidectomy are usually recommended. Prolonged remission was achieved off all medication, without recourse to definitive treatments.

COVID-19 in adults: test menu for hospital blood science laboratories.

INTRODUCTION: Coronavirus disease 2019 (COVID-19), is a respiratory illness caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The Clinical Blood Sciences Laboratory (CBSL) plays a key role in supporting the monitoring and management of patients with COVID-19 disease. OBJECTIVE: To provide a comprehensive CBSL testing protocol to support the medical management of SARS-CoV-2 infection. METHODS: Description of the biochemical, haematological and immunological tests that have a role in the assessment and monitoring of patients with COVID-19 infection. RESULTS: We provide a test menu for clinical laboratories to ensure the effective monitoring, management and prognostication of COVID-19 patients in hospital. CONCLUSION: Given the rapidity with which patients with COVID-19 disease can deteriorate, we recommend regular testing with vigilance paid to the rate and trajectory of change in each of these parameters.

Investigation of the long-term yield of auditing for conformity with the ISO 15189:2012 quality standard in a hospital pathology laboratory.

INTRODUCTION: Pathology laboratories are increasingly seeking accreditation to quality standards to assure Quality of Service (QoS). However, there is little data available regarding the value of this in laboratories with well-established Quality Management Systems (QMS). Moreover, critics of accreditation claim it redirects resources toward trivial issues. Our objective was to investigate the value of auditing for conformity with the ISO 15189:2012 standard in such laboratories. DESIGN: and Methods: In total, 483 Audit-Identified Non-Conformities (AINCs) were documented within our department since transitioning to an ISO 15189:2012 compliant QMS. The potential consequences of these were assessed by three clinical laboratorians who assigned them into categories based on their likely impact. These were: Unlikely (no clear consequences); Possible (potential for poor QoS/harm); and Probable (Likely to cause poor QoS/harm). Additionally, total numbers/severity of Real-Time Non-Conformities (RTNCs) detected outside of auditing were examined to provide additional insight into the effects of accreditation on QoS. RESULTS: According to majority decision: 395 (81.8%) of AINCs were classified Unlikely, 88 (18.2%) were Possible, and none were Probable. The relative proportion of Unlikely AINCs also rose over time. Total numbers and severity of RTNCs dropped in the short-term following transition to an ISO 15189:2012 QMS, but steadily rose thereafter. CONCLUSIONS: Our data suggest auditing for conformity with ISO 15189:2012 standards may be effective in attaining accreditation, but may have diminishing returns in the long-term once the QMS is established, unless there is continual improvement in the audit process to promote better use of resources.