Adult Langerhans cell histiocytosis: An unusual cause of referred knee pain

@#Langerhans cell histiocytosis (LCH) in adults is rare and regarded as an ‘orphan disease.’ The systemic symptoms of LCH can mimic many other undifferentiated diseases seen at the primary care level. Failure to diagnose and delays in referral are common pitfalls in the management of this disease. We present a case of a 34-year-old woman with referred knee pain who was eventually diagnosed with multi-system LCH 4 years after the initial presentation. The mean age of presentation of LCH symptoms in adults is 33. Bone lesions are the frequent presentation of LCH in this age group. Endocrine involvement in LCH is seen in the form of diabetes insipidus (DI), which remains the most common extraskeletal presentation of LCH in adults. In the case discussed here, a definitive diagnosis of LCH was established through tissue biopsy. The spectrum of undifferentiated symptoms underscores the difficulty and delay in making a diagnosis associated with the condition. Most GPs not only face the predicament of initial recognition but also fail to merge presenting symptoms to form a purposeful referral of this elusive disease to a tertiary care unit.

Mechanisms of the antihypertensive effects of Nigella sativa oil in L-NAME-induced hypertensive rats

OBJECTIVES: This study was conducted to determine whether the blood pressure-lowering effect of Nigella sativa might be mediated by its effects on nitric oxide, angiotensin-converting enzyme, heme oxygenase and oxidative stress markers. METHODS: Twenty-four adult male Sprague-Dawley rats were divided equally into 4 groups. One group served as the control (group 1), whereas the other three groups (groups 2-4) were administered L-NAME (25 mg/kg, intraperitoneally). Groups 3 and 4 were given oral nicardipine daily at a dose of 3 mg/kg and Nigella sativa oil at a dose of 2.5 mg/kg for 8 weeks, respectively, concomitantly with L-NAME administration. RESULTS: Nigella sativa oil prevented the increase in systolic blood pressure in the L-NAME-treated rats. The blood pressure reduction was associated with a reduction in cardiac lipid peroxidation product, NADPH oxidase, angiotensin-converting enzyme activity and plasma nitric oxide, as well as with an increase in heme oxygenase-1 activity in the heart. The effects of Nigella sativa on blood pressure, lipid peroxidation product, nicotinamide adenine dinucleotide phosphate oxidase and angiotensin-converting enzyme were similar to those of nicardipine. In contrast, L-NAME had opposite effects on lipid peroxidation, angiotensin-converting enzyme and NO. CONCLUSION: The antihypertensive effect of Nigella sativa oil appears to be mediated by a reduction in cardiac oxidative stress and angiotensin-converting enzyme activity, an increase in cardiac heme oxygenase-1 activity and a prevention of plasma nitric oxide loss. Thus, Nigella sativa oil might be beneficial for controlling hypertension.