TOTAL COLLAPSE OF THE LUNG IN ASPERGILLOSIS

Pathogenetic and serological aspects of pulmonary aspergillosis

Af is an important pathogen of the bronchopulmonary system, and the clinical spectrum encompasses aspergilloma, CNPA, IPA, ABPA, bronchial asthma, and allergic alveolitis. Bronchial carriage may, however, not always be associated with pathological effects. The polymorphism of the aspergillus-related disorders seems mostly to depend upon the different responses of the hosts. This review considers the antigenic composition of Af and specific antibody responses in man in relation to the pathogenesis and diagnosis of the various forms of pulmonary aspergillosis. More than 200 macromolecular components have been listed for Af and more than 30 antigens found to react with human sera. Serum antibodies to Af are common in healthy subjects. Schønheyder and his associates (A-L) have shown that IgG, IgA and IgM antibodies in healthy subjects are directed towards antigens to which also patients with aspergillosis strongly react. With immunofluorescent staining these antigens were found to be associated with hyphal walls, and a MW 470,000 fraction from ruptured mycelium was most reactive in ELISA. The respiratory tract appears to be the major route for exposure since the humoral responses include IgA class antibodies, and sIgA antibodies are found in bronchial secretions. Moreover, IgG antibody levels to the MW 470,000 fraction correlate with occupational exposure and smoking habits. In patients with cystic fibrosis high IgG antibody levels to MW 470,000 and MW 25,000-50,000 antigen fractions were associated with the carriage of Af in the sputum. An individual patient's level of IgA antibodies to the MW 470,000 fraction was inversely related to the Af carrier rate, and this was also true for IgE dependent reactivity to Af antigens. These observations indicate that IgG antibodies to some antigens mirror the extent of antigenic exposure, whereas some IgA and IgE antibodies may play a protective role against bronchial colonization with Af. IgG antibody determinations by ELISA were found to provide a higher diagnostic efficacy in pulmonary aspergillosis than IgA antibody assays. With IgG antibodies there were statistically significant differences between patients and the controls and there was little overlap of ELISA values between the groups. The fractions of MW 250,000 with catalase activity and MW 25,000-50,000 with protease activity, were most suitable for serological diagnosis. A gel immunoelectrophoretic assay proved Af catalase to be a major diagnostic antigen in patients with aspergilloma or with an apical aspergillus lung infiltrate.(ABSTRACT TRUNCATED AT 400 WORDS)

Allergic broncho-pulmonary aspergillosis: the radiological appearance during long-term follow-up

The radiographs of 100 patients with allergic bronchopulmonary aspergillosis were examined to assess the type and distribution of abnormalities seen during long-term follow-up. Lobar shrinkage occurred almost exclusively in the upper zones but other abnormalities were distributed throughout both lungs. Bronchial wall thickening was the commonest lesion observed and was usually a permanent finding. Consolidation was commonest in the perihilar regions, persisted for up to 20 weeks when transient and was a permanent finding in 10 patients. Dilated bronchi were noted to change in calibre with exacerbations and remissions of the condition. Episodes of transient collapse were segmental, lobar or involved a whole lung. Permanent collapse was always segmental. Massive shadowing, band shadows and 'gloved fingers' were seen less frequently than expected and cavitation was rare. In some patients the chest radiograph was normal between exacerbations of the disease.

Lung collapse caused by allergic bronchopulmonary aspergillosis in non-asthmatic patients

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Allergic aspergillosis: review of 32 cases

The clinical, radiographic, and laboratory findings have been reviewed in a series of 22 patients with definite and 10 with probable allergic aspergillosis. Episodes of segmental shadowing occurred most frequently in the upper lobes and tended to recur in the same segment. Radiologically visible mucoid impaction of a large bronchus was demonstrated in eight cases, and saccular bronchiectasis in six cases, in the affected segments. Two patients have recovered, eight continued to experience episodic symptoms and shadows for up to 13 years, and 11 are on steroid therapy with relief of airways obstruction and prevention of further lung shadows. Four, together with five others who probably represent a late stage of the disease, have upper lobe contraction. One patient developed aspergillomas and one died with invasive aspergillosis. Sputum has remained positive in all except one patient. Precipitins were present in all cases. They varied widely in strength and appeared to be more closely related to the amount of antigenic exposure than to the severity of the allergic manifestations. Allergy to Aspergillus fumigatus probably plays a dominant role in the symptomatology of those with asthma of late onset; evidence of underlying atopic diathesis and of increased spore exposure could usually be adduced in these patients. A quantitative interaction of atopic diathesis and contact with a growing source of fungal antigens will result in a locally florid bronchial reaction, with plugging and subsequent dilatation. The peripheral shadows are consistent with areas of collapse distal to bronchial occlusion. The frequency and distribution of mucoid impaction found in this series suggest that allergic aspergillosis may be a major cause of this uncommon syndrome, which could represent an exaggerated form of bronchial plugging.

Treatment of bronchopulmonary aspergillosis with observations on the use of natamycin

The problems of treatment in bronchopulmonary aspergillosis are discussed and illustrated by 11 case reports—four with aspergilloma, six with allergic aspergillosis, and two with probable allergic aspergillosis. A simple and effective treatment of aspergilloma, by local surgical evacuation of the cavity followed by irrigation with natamycin (Pimaricin), is described in three cases. Prior treatment of these cases with inhalations or intrabronchial instillations of natamycin was of doubtful benefit. The therapy of allergic aspergillosis is reviewed and an active approach is urged, based on the probable pathogenesis of the disease. This includes consideration of physical methods of removing bronchial plugs, mucolytic agents, steroids, and antifungal drugs given by aerosol in the absence of any that are suitable for systemic use. Steroids improved ventilatory function and were effective in resolving and preventing further episodes of pulmonary eosinophilia, but not usually in clearing the fungus from the bronchial tree, probably because permanent damage had already been sustained; they also carry the theoretical risk of allowing fungal invasion. Natamycin inhalations alone are considered of little value in the active disease, although their place in prophylaxis and when used with steroids remains to be evaluated. Mucolytic agents may help to clear the bronchial secretions, especially when these have become chronically impacted.

Pulmonary aspergillosis in two families

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