Needle Biopsy as an Aid to the Precise Diagnosis of Intrathoracic Disease

The place of needle biopsy of the lung and pleura in the diagnosis of intrathoracic disease was assessed by means of an analysis of the results of this procedure in 78 cases involving 111 separate biopsy attempts. The Vim-Silverman needle was used throughout. Needle biopsy of the lung, restricted to cases with localized radiological lesions peripherally situated and suggesting neoplasm, yielded a specific diagnosis in 29 of 48 patients. The comparison with other diagnostic aids, bronchoscopy, sputum cytology and scalene node biopsy, was favourable, at least in the case of peripheral tumours. There were eight complications, only three of which were of significance. Needle biopsy of the pleura proved to be a less rewarding procedure, a specific diagnosis being obtained in only seven of 30 cases. There were, however, no serious complications with this latter procedure. It was concluded that needle biopsy is of some value as a relatively safe addition to diagnostic techniques in chest disease.     

Fine-needle Aspiration Biopsy of Spleen in Diagnosis of Generalized Amyloidosis

Fine-needle aspiration biopsy of the spleen was performed on 18 patients shown to have amyloid deposits in other organs and on 17 control patients being investigated for proteinuria. Of the 18 patients with amyloid disease smears of splenic aspirate were positive in all cases, renal biopsy was positive in 16 out of 16 cases, and rectal biopsy was positive in seven out of 11 cases. None of the splenic smears were positive in the 17 control patients and no amyloid was found in the kidney in 15 of these patients on whom renal biopsy was performed. Splenic aspirate biopsy seems to be a simple and safe procedure for the diagnosis of amyloidosis. It is as accurate as renal biopsy and more accurate than rectal biopsy.     

Immunofluorescence as an Aid in the Early Diagnosis of Trichinosis

The established serological tests for trichinosis are often negative during the period when laboratory investigation is most likely to be useful.Another serological test, the immunofluorescence test, appears to be more promising in this respect. The results were based on studies involving experimental animals and human patients. In two rabbits orally infected with Trichinella spiralis larvae, antibodies were demonstrable by immunofluorescence on the fourth day after infection, by complement fixation on the eighth and tenth days, and by the precipitin test on the thirteenth and twenty-eighth days, respectively. In three human cases the immunofluorescence antibody test was positive two weeks (the earliest blood samples available) after onset, while precipitin and complement fixation tests did not become positive until the end of the fourth week. The immunofluorescence test thus becomes positive at least two weeks earlier than the other two, a factor which undoubtedly increases its value in diagnosis.     

Catalase Test as an Aid to the Identification of Enterobacteriaceae

Although the catalase test has been used for many years for rapid differentiation of the genera of gram-positive organisms, little has been said about its use in the family Enterobacteriaceae. It was further noted that a wide variety of methods exist for the execution of the catalase test, that there is no universally accepted strength specified for the hydrogen peroxide, and that no gradations for the vigor and speed of the reaction have been mentioned. Under the conditions of the clinical laboratory, we have developed a simple, rapid, and accurate method for the catalase test that has been of great value as an aid in the identification of the Enterobacteriaceae. With 3% H(2)O(2), it was observed that Serratia, Proteus, and Providencia were vigorous catalase reactors. Only Salmonella and rare Escherichia, Enterobacter, and Klebsiella isolates were moderate catalase reactors. Escherichia and Shigella strains were mostly nonreactive, with less than one-third weekly (+) reactive, whereas most Enterobacter strains tended to be weakly reactive. Klebsiella strains were divided equally between nonreactive and weakly reactive. In practice, this test was also of great value in discerning nonpigmented Serratia cultured from the hospital environment and in detecting mixed flora containing nonspreading Proteus.