ACUTE RHEUMATISM 193 



streptococci and staphylococci. True diphtheria of the con- 

 junctiva caused by the Klebs-LorHer bacillus also occurs, 

 whilst in gonorrha'al conjunctivitis, often of an acute purulent 

 type, the gonococcus is present (p. 225). 



Diplo - bacillus of Conjunctivitis. This organism, discovered by 

 Morax, is a small plump bacillus, measuring 1 x 2 /*, and usually occur- 

 ring in pairs, or in short chains of pairs (Fig. 63). It is non-motile, 

 does not form spores, and is decolorised by Gram's method. It does not 

 grow on the ordinary gelatin and agar media, the addition of blood or 

 serum being necessary. On serum it forms small rounded colonies 

 which produce small pits of liquefaction ; hence it has been called the 

 bacillus lacunatus. In cultures it is distinctly pleomorphous, and 

 involution forms also occur. It is non-pathogenic to the lower animals. 



Acute Rheumatism. There are many facts which point to 

 the infective nature of this disease, and investigations from this 

 point of view have yielded important results. Of the organism 

 isolated, the one which appears to have strongest claims is a 

 small coccus observed by Triboulet, and by Westphal and 

 Wassermann, the characters and action of which were first 

 investigated in this country by Poynton and Paine. It is now 

 usually spoken of as iho^nicrococcus rheumaticus. The organism 

 is sometimes spoken of as a diplococcus, but it is best described 

 as a streptococcus growing in short chains ; in the tissues, how- 

 ever, it usually occurs in pairs. It is rather smaller than the 

 streptococcus pyogenes, and although it can be stained by Gram's 

 method, it loses the colour more readily than the streptococcus. 

 In the various media it produces a large amount of acid, and 

 usually clots milk after incubation for two days ; on blood agar 

 it alters the haemoglobin to a brownish colour. Its growth on 

 media generally is more luxuriant than that of the streptococcus, 

 and it grows well on gelatin at 20 C. Intravenous injection 

 of pure cultures in rabbits often produces polyarthritis and 

 synovitis, valvulitis and pericarditis, without any suppurative 

 change lesions which it is stated are not produced by the 

 ordinary streptococci (Beattie). In one or two instances 

 choreiform movements have been observed after injection. The 

 organism is most easily obtained from the substance of inflamed 

 synovial membrane where it is invading the tissues ; a part 

 where there is special congestion should be selected as being 

 most likely to give positive results. It is only occasionally to 

 be obtained from the fluid in joints. It has also been cultivated 

 from the blood in rheumatic fever, from the vegetations on the 

 heart valves, and from other acute lesions ; in many cases, how- 

 ever, cultures from the blood give negative results. Poynton 

 13 



