Developing best practice for fungal specimen management: audit of UK microbiology laboratories

This study represents an audit of microbiology laboratories in the UK to ascertain whether they are aware of, or follow, the Health Protection Agency (HPA) National Standard Methods Standard Operating Procedure (NSM SOP) for the investigation of dermatological specimens for superficial mycoses, or use a locally adapted version. A questionnaire audit was distributed to 179 NHS microbiology laboratories throughout England, Wales, Scotland and Northern Ireland. The NSM SOP was followed by 92% of laboratories for the microscopy of dermatological samples; light microscopy/ KOH digestion was used by 63% and fluorescence microscopy/KOH digestion by 29% of laboratories. Preliminary reports post-microscopy were issued by 98% of laboratories, with 93% issuing reports within 48 hours. Adherence to the NSM SOP guidelines for culture was low; only 34% of laboratories incubated microscopy-negative specimens for the recommended 14 days, while approximately 60% incubated microscopy-positive specimens for 21 days. The culture medium recommended by the NSM SOP was used in 82% of laboratories. Comments were added to culture reports by 51% of laboratories; most were added manually and comments varied between laboratories. Nail samples were the most common sample received from primary care, followed by skin and hair. These results show no significant difference in the rate of microscopy positives versus culture positives. Microscopy and culture are the easiest and cheapest methods available to UK laboratories for the investigation of suspected superficial fungal infections. Although most laboratories included in this audit claimed to follow the NSM SOP for microscopy and culture, these results show that the techniques used vary throughout the UK. To maximise the service provided to primary care, UK laboratories should use standardise methods based on the NSM SOP.