P324 A CASE OF ATRIAL MYXOMA WITH UNUSUAL CLINICAL PRESENTATION

Myxoma (mx) is the most frequent adult cardiac tumour, that often poses a difficult diagnostic challenge due to the variety and aspecifity of presenting clinical signs. Alongside the more typical clinical onset caused by intracardiac obstruction and systemic embolization, mainly at cerebral level, a mx may initially manifest itself with nonspecific systemic symptoms such as fever, weight loss, fatigue, skin rash, myalgia and arthralgia. We present the case of a 58–year–old woman diagnosed in December 2018 with idiopathic, serum–negative arthritis of the metacarpophalangeal joint of the first finger of the right hand, treated with methotrexate (Reumaflex 10 mg/week s.c.), hydroxychloroquine sulphate (Paquenil 200 mg/day per os) and corticosteroids cycles; in January 2021, this therapy was suspended by the patient (pt) as ineffective. In April 2021, pt was admitted for bilateral SARS–CoV–2 pneumonia. As dyspnoea and fatigue persisted during moderate physical activity (NYHA class II), the pt underwent a cardiological examination on 13 August, when echocardiographic diagnosis of a left atrial mass with the appearance of a mx was made. Interleukin–6 (IL–6) was assayed for a suspected relationship between the cardiac tumour and rheumatic symptoms and was found to be elevated (490 pg/m)l. On 23 August, cardiac surgery was performed to remove the left atrial mass by right minithoracotomy. Histopathological examination confirmed that the 3.5 x 2.5 x 1.5 cm neoformation was a mx. On 1 September, strong attenuation of joint pain and IL–6 reduction to 107 pg/ml was detected. On 9 October, resolution of rheumatic symptoms and normalisation of IL–6 to 3.7 pg/ml (N.V < 7) occurred. This clinical case is emblematic of the long time that sometimes can elapse between the first clinical manifestation and the diagnosis of mx. Also the widespread use of echocardiography did not significantly reduce the diagnostic delay when cardiac symptoms are absent. In a large number of cases, onset symptoms mimicking autoimmune connective tissue disease are reported for 5% (“Clinical presentation of left atrial cardiac myxoma. A series of 112 consecutive cases” Medicine (Baltimore) 2001 May;80(3):159–729). The monoarticular localisation we describe is however unusual. Finally, our observation confirms that the association between mx and systemic symptoms is most likely due to IL–6 synthesis by tumour cells.

Biological monitoring of exposure to organophosphorus insecticides by assay of urinary alkylphosphates: influence of protective measures during manual operations with treated plants

Biological monitoring was carried out by assaying urinary dimethylated alkylphosphates [dimethyldithiophosphate (DMDTP), dimethylthio-phosphate (DMTP), and dimethylphosphate (DMP)] in 11 workers exposed to chlorpyrifos-methyl and azinphosmethyl during operations in a previously sprayed peach orchard. The subjects were divided into groups on the basis of the protective clothing worn. The results were compared with those of a reference group of 99 subjects not occupationally exposed to organophosphorus insecticides. The hand-wash liquid of the workers was also analyzed to evaluate skin contamination. Significantly higher levels of urinary excretion of alkylphosphates were found in all groups than in unexposed controls (Student's t test). A good correlation was found between quantities of the active ingredients on the hands and urinary excretion of total dimethylated alkylphosphates (r = 0.788) and of DMTP (r = 0.749) and DMP (r = 0.790) alone. The correlation between azinphos-methyl on the hands and urinary excretion of DMDTP was poor (r = 0.069). Under the working conditions investigated, the main route of absorption seems to be via the skin. Respiratory absorption, however, also appears significant in view of the difference in urinary excretion of dimethylated alkylphosphates found between subjects with and without face masks.