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This guideline (last updated in March 2021) proposes a set of consensus recommendations from the perspective of pathology and laboratory medicine.

Initially during COVID workload halved before increasing three fold due to expanded criteria and catch up testing. This put considerable strain on the laboratory. Reduced endoscopy capacity was manged by risk stratification of 2WW patients by FIT testing. The age criteria were widened increasing numbers by 6%. The % positive FIT tests was the same in primary and secondary care suggesting similar risk. Expanded FIT testing is likely to remain in place and is predicted to reduce endoscopy numbers.

Impact of LDL formula and apo B quantification on UK PCSK9i and ESC/EAS treatment thresholds in patients being investigated for familial combined hyperlipidaemia. Martin equation provides a greater estimation of LDL-C values. This could result in demonstrating suboptimal treatment for patients whom LDL-C levels are underestimated using Friedewald calculation and potentially make more people (at most 12%) eligible for PCSK9i therapy according to UK thresholds. Control as indicated by ApoB was better than LDL-C therefore ApoB targets do the converse in this population with suspected FCH i.e. they would suggest less need for treatment escalation and demonstrate that more of the population is treated to target than the LDL-C suggests.

The limitations in commercial insulin assays require external referral to laboratories for a full biochemical investigation. Here a case is discussed that aptly portrays the limitations associated with the Roche Elecys Insulin assay when insulin is administered surreptitiously, resulting in a hyperinsulinism picture without the raised insulin concentration.

Galactose-1-phosphate uridyltransferase (Gal-1-PUT or GALT) quantitation is important in the diagnosis of Classical Galactosaemia. An HPLC-MS/MS assay has been set up, optimised and validated in our lab at North Bristol NHS Trust. Benefits include no radioactivity, smaller sample volume, larger batch sizes and improved precision. A summary of the method, its performance characteristics, and comparison with the previous assay is presented, alongside sample requirements and clinical indications.

Cannabis is a widely used recreational drug obtained from the plant Cannabis sativa. The plant produces chemicals of which the most psychoactive agent is Δ9-tetrahydrocannabinol (THC). THC is metabolized in the body to THC-OH and then to the psychotropically inactive metabolite THC-COOH. The current method using GC-MS requires extensive samples preparation and long run times. We have developed a method to measure THC and its metabolites on the LC-MS/MS for forensic use.

A common dilemma faced by Clinical Biochemistry teams when establishing commenting practices is whether primary care requestors would like us to prioritise the speed of reporting abnormal results or the addition of interpretive comments to aid diagnosis and further investigation. Reported here are the findings of a GP survey completed as part of an ongoing review of the commenting practices at Derriford Combined Laboratory, which aimed to find a consensus from our users regarding the processing of abnormal sodium, potassium, and calcium results. The results show that although speed of reporting is often preferred to the addition of interpretive comments, surveys such as these are useful to identify those results where primary care requestors would value input from the Duty Biochemist to aid patient management.

Type I diabetes patients with end stage renal failure are suitable candidates for simultaneous pancreas and kidney (SPK) transplantation. C-peptide is used to monitor graft function. This study aimed to look at biological variation and determine a reference interval for c-peptide in SPK patients. 347 c-peptide results from 26 patients were obtained from the laboratory database. The quoted reference interval for c-peptide for a healthy fasting individual with normal blood glucose, is 350-1800 pmol/L.  For SPK patients a reference interval of 441 – 3068 pmol/L may be more appropriate.