Long-term complications of sulphur mustard poisoning in severely intoxicated Iranian veterans

Sulphur Mustard (SM) is an alkylating chemical warfare agent that was widely used during the World War I and in the Iran-Iraq conflict. Delayed complications of SM in different organs and their severity correlations have not previously been reported. Dermatological, ophthalmological, neurological and respiratory examinations, as well as spirometry, gasometry, high resolution Computed tomography scanning of the chest, electromyography, nerve conduction velocity, cell blood counts, flow-cytometric analyses, and measurement of serum immunoglobulins and complement factors were performed on all severely SM poisoned veterans in the province of Khorasan, Iran. Haematological and immunological studies were also performed on a control group consisting of 35 healthy male subjects. The severity of dermal, ocular and respiratory complications were classified into four grades and their correlations with each other as well as with the haematological and immunological parameters were determined, using Spearman's rank correlation test. Forty male patients (aged 43.8 +/- 9.8 years) with confirmed SM poisoning 16-20 years after the exposure were studied. The most common complications were found in the lungs (95%), peripheral nerves (77.5%), skin (75%), and eyes (65%). WBC, RBC, haematocrit (HCT), IgM, C3, and the percentages of monocytes and CD3(+) lymphocytes were significantly (P < 0.042) higher and the percentage of CD1.6 + 56 positive cells was significantly (P = 0.006) lower in the patients than in the control group. The severity of respiratory complications revealed a significant correlation with the severity of ocular complications (r = 0.322, P = 0.043), as well as with the haemoglobin (r = 0.369, P = 0.024) and HCT (r = 0.470, P = 0.003). Although late complications of SM poisoning in the skin, eyes, and respiratory system are mainly due to its direct toxic effects, the neuromuscular, haematological and immunological complications are probably the result of systemic toxicity.