A qualitative study of knowledge, behaviour and attitudes regarding vitamin D acquisition among patients with photosensitivity disorders.

BACKGROUND: Cutaneous exposure to sunlight is a major source of vitamin D. Individuals with photosensitivity disorders have symptoms provoked by sunlight and may not achieve the brief sunlight exposures that convey vitamin D acquisition. OBJECTIVE: To explore knowledge, behaviour and attitudes towards vitamin D and its acquisition in patients with photosensitivity. METHODS: Patients (n = 19) diagnosed with solar urticaria, erythropoietic protoporphyria or polymorphic light eruption at a specialist photoinvestigation centre participated in semi-structured focus groups to discuss vitamin D knowledge, acquisition behaviours and attitudes towards vitamin D acquisition through sunlight and diet. Discussions were analysed by thematic analysis using MAXQDA11. RESULTS: Knowledge of vitamin D was variable. There was good awareness that sunlight exposure is an important source but knowledge of dietary sources was poor. Patients had little concern for their own vitamin D status prior to attending the photoinvestigation centre. Most patients avoided sunlight exposure, were unable to achieve the guidance on sun exposure for healthy individuals and were aware this could affect their vitamin D status. Use of oral vitamin D supplements was common, and all were willing to consider supplements if required. Patients recommended improving education of clinicians to increase patient awareness of vitamin D, CONCLUSIONS: More targeted guidance is required on acquisition of vitamin D for patients with photosensitivity, supported by increased patient and clinician education.

Quantifying bile acid malabsorption helps predict response and tailor sequestrant therapy.

Although recognised as a cause of chronic diarrhoea for over forty years, diagnostic tests and treatments for bile acid malabsorption (BAM) remain controversial. Recent National Institute for Health and Care Excellence (NICE) guidelines highlighted the lack of evidence in the field, and called for further research. This retrospective study explores the BAM subtype and severity, the use and response to bile acid sequestrants (BAS) and the prevalence of abnormal colonic histology. 264 selenium-75-labelled homocholic acid conjugated taurine (SeHCAT)-tested patient records were reviewed and the severity and subtype of BAM, presence of colonic histopathology and response to BAS were recorded. 53% of patients tested had BAM, with type-2 BAM in 45% of patients with presumed irritable bowel syndrome. Colonic histological abnormalities were similar overall between patients with (29%) or without (23%) BAM (p = 0.46) and between BAM subtypes, with no significant presence of inflammatory changes. 63% of patients with BAM had a successful BAS response which showed a trend to decreased response with reduced severity. Colestyramine was unsuccessful in 44% (38/87) and 45% of these (17/38) were related to medication intolerance, despite a positive SeHCAT. 47% (7/15) of colestyramine failures had a successful colesevelam response. No patient reported colesevelam intolerance. Quantifying severity of BAM appears to be useful in predicting BAS response. Colesevelam was better tolerated than colestyramine and showed some efficacy in colestyramine failures. Colestyramine failure should not be used to exclude BAM. Colonic histology is of no relevance.