Yet there is something special in acute rheumatism which perhaps has to do with the occurrence as well as the severity of the cerebro-spinal symptoms and of the hyperpyrexia; viz. the long duration and severity of the pain, and the number and importance of the parts, in addition to the articulations, which are one after the other or simultaneously involved in severe inflammation--peri-, endo-, myocardium, lungs, pleura, etc. Perhaps in no other acute febrile disease are so many distinct and important organs involved in inflammation at the same time or in rapid succession; and it is no wonder that the functions of the nervous system should in consequence become greatly depressed, exhausted, or disturbed. The kidneys appear very rarely to suffer serious disease in acute rheumatism, if we except embolism of their arteries due to endocarditis; and it is very doubtful whether the rare instances[100] in which an acute parenchymatous nephritis has been observed in acute rheumatism can be referred to direct rheumatic inflammation, or not, rather, to the operation of the exposure which induced the rheumatism. Further investigation is needed to determine whether interstitial nephritis is even very exceptionally an indirect consequence of rheumatism, as Lancereaux admits. [Footnote 100: See DaCosta's cases 1 and 2, _Cerebral Rheumatism, lib. cit._; case 1 certainly favors the view that either the rheumatic poison, if there be such, or the constitutional disturbance incident to acute polyarticular rheumatism, may sometimes produce nephritis. See also a case by A. Deroye, Thèse, Doctorat, Paris, 1874, quoted by P. Coubere in _Contribution à l'Étude des Complications Renales du Rheumatisme Artic. Aigue_, Paris, 1877.] The other complications, being of less importance, must be but barely alluded to. A pharyngitis attended with severe dysphagia and high fever occasionally precedes the other symptoms or occurs in the early stage of the disease. Gastralgia, enteralgia, simple serous diarrhoea, and dysentery also rarely occur in acute rheumatism. That they are sometimes, at least, truly rheumatic appears probable from the circumstance that they may precede, follow, or alternate with the articular affection, and are all intensely painful. I have but once met with acute peritonitis as a complication of acute rheumatism; the immunity of this serous membrane from rheumatic inflammation is an inexplicable anomaly in view of the proclivity of the pericardium and pleura to that process. Cystitis and orchitis are rare.