Eight caaes of this condition are described, the patients being four Ceylonese, three Indians, and one Chinese, all males except one. Symptoms consisted of breathlessness and cough, sputum being sometimes purulent and occasionally blood-stained. Six of the patients complained of loss of weight, and in one, a Ceylonese schoolboy, this was the only presenting symptom. The authors found the most troublesome complaint to be a paroxysmal cough which was always worst at night. On clinical examination rhonchi were heard scattered throughout both lung fields in five cases, the lungs being clear in the other three. X-ray examination showed characteristic mottling of both lungs in four cases and of one lung in one case; another showed increased vascular markings, while in two the lungs were clear. Sputum was examined for tubercle bacilli and mites but none were found. The technique used for searching for mites is not described. A marked eosinophilia was found in all cases, the highest count recorded being 33, 264 eosinophils per cmm.Treatment consisted of arsenic, given in the form of neoarsphenamine, six injections of 0.3 gm. in six cases, and stovarsol 4 grains t.d.s. for seven and ten days respectively in the other two. Four of the patients were cured, three were improved, while one was showing a favourable response although treatment had not been completed.The author emphasizes the importance of performing repeated blood counts in order to avoid missing this condition. Out of the eight cases which he describes, one had been wrongly diagnosed as pulmonary tuberculosis and three as bronchial asthma. One of the latter had an initial eosinophil count of 4, 092 which rose to 17, 700 three weeks later. H. T. H. Wilson
The intradermal test using as antigen a 1 per cent saline extract of Dirofilaria immitis powder was performed in Singapore on 69 persons with eosinophilic lung, 32 with mild eosinophilia, 49 with filariasis, 75 normal Asians, and 66 normal Britishers. The test was positive in 100 per cent of the cases of eosinophilic lung, 73.5 per cent of the filariasis group, 59.4 per cent of cases of mild eosinophilia, 53.3 per cent of normal Asians, and 4.5 per cent of the Britishers. The filarial complement fixation test using a 1 per cent alcoholic extract of the same antigen gave a positive rate of 100 per cent in the eosinophilic lung group, whereas only 24.5 per cent of the filariasis patients gave a positive reaction. Skin sensitivity to D. immitis antigen persisted in the cases of eosinophilic lung even when the previously positive serologic reactions had become negative following treatment with diethylcarbamazine. Therefore, the intradermal test cannot be useful in the diagnosis of either filariasis or eosinophilic lung in Singapore. In view of the skin sensitivity to a filarial antigen demonstrated in patients suffering from eosinophilic lung, the etiologic possibility of an infection by a species of filarial worm found normally in nonhuman hosts is discussed.
The above survey based on a study of single stool specimens from 569 patients, drawn from a hospital population belonging to different ethnic groups and having different cultural backgrounds, failed to indicate an association between intestinal helminth infection and eosinophilic lung. The higher prevalence of eosinophilic lung in Indians than in the other ethnic groups, as reported previously, cannot be explained on a basis of differences in the prevalence of the intestinal helminths, Ascaris lumbricoides, hookworm, Trichuris trichiura and Strongyloides stercoralis.
Sera taken fortnightly from fourteen patients with eosinophilic lung (tropical eosinophilia) were tested by complement fixation with ethanol extracts of Dirofilaria immitis, Ascaris lumbricoides, Toxocara canis, Gnathostoma procyonis, Fasciola gigantica and Dipylidium caninum. Initially, sera from ten patients had high antibody titers with each of the extracts while antibodies were not detected in sera from the other four; after treatment with diethylcarbamazine the high titers decreased. It is concluded that the reactions obtained with these various extracts do not indicate infection with any particular helminth.
Saline extracts of ether-treated Dirofilaria immitis, Ascaris suum, and Ancylostoma spp. were used in indirect hemagglutination tests of serum from 164 patients with a diagnosis of eosinophilic lung and 114 persons with other diseases or no disease (blood donors). In the first group, positive reactions with one, two or all three antigens were obtained in 89 percent of cases and the titers, at medium or high levels in 77 percent, decreased after treatment with diethylcarbamazine. In the other group, antibodies were demonstrable in the serum of only 22 percent of cases and titers usually were low. These observations indicate the presence of several antigen-antibody systems, some of which appear to be specific. With extracts of Dirofilaria the indirect hemagglutination and the complement-fixation tests were similar in sensitivity and specificity, but the results from neither test appeared to indicate infection with a specific worm.