Vocal cord biopsy leading to the diagnosis of hyperlipidaemia.

A 33 year old man presented with three months of persistent hoarseness with no preceding upper respiratory tract infection. He was otherwise a healthy young policeman and he was a non-smoker. A benign looking polyp was discovered on microlaryngoscopic examination at the anterior end of the left vocal cord adjacent to the anterior commissure. This was biopsied and subsequent histological examination showed a polypoid fragment of respiratory tract mucosa with abundant fibrinoid material in its core, as would be expected in a typical vocal cord polyp. However, numerous foamy histiocytes were also present, with most forming sheets surrounding blood vessels (fig 1A, B). This raised the suspicion of hyperlipidaemia. Subsequent blood tests revealed a random cholesterol value of 9.2 mmol/litre (normal range, 2.9–5.2) and triglycerides of 6.78 mmol/litre (normal range, 0–2 fasting). His general practitioner was informed and a repeat fasting blood test was performed. This showed the fasting cholesterol and triglyceride values to be 7.3 mmol/litre and 2.86 mmol/litre, respectively. Therefore, he was started on treatment for hyperlipidaemia. Foamy histiocyte collections are well described in the gastrointestinal tract. To the best of our knowledge, however, this is the first report of the presence of foamy histiocytes in the larynx. All studies on the association between tissue collections of foamy histiocytes and disorders of lipid metabolism have been done on patients with palpebral xanthelasma. Although not all patients with xanthelasma have dyslipidaemia, xanthelasma is a good marker for dyslipidaemia, and thus an indication for a full lipid profile study. 7 Our case is unique in that the patient’s hyperlipidaemia was diagnosed through an initial presentation of hoarseness. This is the first ever reported case to show an association between a tissue collection of foamy histiocytes, other than palpebral xanthelasma, and hyperlipidaemia. This may be a very rare association, or it may be that we have not previously paid enough attention to the presence of foamy histiocytes in our vocal cord biopsies. Considering the prevalence of dyslipidaemia in developed nations, the presence of foamy histiocytes in the larynx may be more common than we expect.