Alkaptonuria (endogenous ochronosis) is a rare metabolic disorder caused by a deficiency of homogentisic acid oxidase, an enzyme responsible for the metabolic degradation of tyrosine. Patients with alkaptonuria commonly present with joint pain owing to degenerative arthritis. Other affected patients may present with pigmentation of the ear cartilage and sclera. This article reports a case of aortic stenosis associated with ochronosis in a 48-year-old man who presented with severe cardiac failure. He had no previous diagnosis of alkaptonuria, which was confirmed by mass spectrometry analysis of urine. The pathogenesis of cardiovascular ochronosis is unclear, but is probably related to the extensive extracellular deposits of ochronotic pigment in the cardiac tissue.A 48-year-old Palestinian man was admitted to University College London Hospitals with a 2-month history of gradually increasing shortness of breath on exertion and a 3-week history of exertional chest pain. He had a 9-year history of type 2 diabetes treated with insulin, complicated by peripheral neuropathy. He was diagnosed with severe congestive cardiac failure, and an echocardiogram showed a severely impaired left ventricle. The ejection fraction was 25%. A calcified aortic valve had severe stenosis, with a valve area of 0.65 cm 3 and a peak gradient of 76 mm Hg. An echocardiogram showed left ventricular hypertrophy, with no acute ischaemic changes. Troponin T was negative. He was put forward for a heart transplant, but was declined in view of end-organ damage as a result of having diabetes. A coronary angiogram showed considerable disease in the left anterior descending artery (LAD) and obtuse marginal vessels. The right coronary artery was dominant and normal.He underwent replacement of the aortic valve by a mechanical heart valve (St Jude Medical) along with a single coronary artery bypass graft (left internal mammary artery to LAD), 2 months after his initial presentation. At operation, it was noted that the entire inside wall of the aorta was covered in black patches that extended down into the endothelium of the left ventricle and involved the aortic valve. Black patches were also seen on the inside of the LAD, which itself showed marked atherosclerosis. He recovered uneventfully from the operation, and on follow-up had satisfactory exercise tolerance and no angina. His only complaint, which dates back to the time of the operation, was widespread joint pain, particularly affecting the knees and hands. Macroscopic examination of the valves showed calcified valve leaflets covered in black patches (fig 1). Microscopic examination showed the deposition of a brown pigment in the body of the valve, which was associated with nodules of calcium (fig 2). Staining with Masson-Fontana and Von Kossa, histochemical stains, for melanin and calcium respectively, were carried out on the valve section. MassonFontana was negative and Von Kossa confirmed the presence of calcium in the body of the valve but did not explain the additional brown pigment deposited i...
Methylene blue is a chromophore dye known for its photosensitizing properties. It is also administered intravenously as a tracer in parathyroid surgery to identify abnormal glands. We describe 2 cases of acute methylene blue-induced phototoxicity in patients who underwent parathyroidectomy. Both patients developed an acute vesiculopustular inflammatory rash on the anterior neck corresponding to the site exposed intraoperatively to overhanging surgical lights. One of the patients also developed a bulla on her finger at the site of attachment of the oxygen probe. Biopsies were taken from both patients at different time points. The histological findings included destruction of sebaceous glands and deposition of diastase-periodic acid-Schiff-positive hyaline material around dermal blood vessels. These features are similar to those seen in skin treated with photodynamic therapy and systemic photosensitivity disorders such as the porphyrias. The wavelengths of light emitted by the surgical lights and oxygen probe overlap with the absorption spectrum of methylene blue. This resulted in excitation of the systemically administered methylene blue at exposed sites, with resultant local tissue damage and a phototoxic reaction.
We conclude that pathological examination of bronchial biopsies is unlikely to be useful in the diagnosis of chronic cough in non-smokers.
A 54-year-old man initially presented with a 2-year history of non-itchy, well-demarcated, erythematous scaly plaques over his face (Fig. 1a). On histological examination of skin biopsy samples, a lichenoid inflammatory infiltrate, with necrotic keratinocytes and overlying areas of parakeratosis, was seen. Direct immunofluorescence was negative, and tests for antinuclear and anti-double-stranded DNA antibodies were also negative. Based on the clinical and histological findings, a diagnosis of discoid lupus erythematosus (DLE) was made at that time.Over the subsequent 8 years, the patient received a number of treatments, including clobetasol propionate 0.05%, tacrolimus 0.1% ointment, prednisolone, acitretin, hydroxychloroquine, mepacrine and dapsone, all without benefit. Within 2 years of the initial diagnosis, the patient started to develop non-itchy lichenoid papules that coalesced to form linear patterns over his abdomen and toes (Fig. 1b). Persistent painless ulceration over the hard palate (Fig. 1c) and chronic conjunctival hyperaemia were also noted. The atypical clinical features and a history of improvement when the patient went on holiday in sunny climates suggested that DLE was unlikely. The patient was prescribed a course of ultraviolet (UV)B phototherapy, but without benefit.Histological examination of a repeat skin biopsy taken from the abdomen revealed focal parakeratosis, irregular acanthosis, a chronic lichenoid inflammatory infiltrate in the papillary dermis with focal basal-layer degeneration and abundant necrotic keratinocytes at the tip of the rete ridges (Fig. 2). An oral biopsy sample from the soft palate had similar features, including focal parakeratosis and a dense lichenoid inflammatory infiltrate with basal-layer degeneration. On Figure 1 (a) Well-dermarcated erythematous scaly plaques over the face; (b) lichenoid papules coalescing to form a linear pattern over the abdomen; (c) lichenoid ulceration over the hard palate.
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