DUKES' " FOURTH DISEASE " Dukes' "Fourth Disease" is a mild affection like rubella but with a rash resembling scarlet fever as the rubella rash resembles measles, or we might say that it resembles closely the abortive form of scarlet fever.
One naturally asks upon what observations does Dukes base his opinion that the "Fourth Disease" exists as a separate clinical entity. In 1892, Dukes was asked advice concerning sixteen cases supposed to be scarlet fever. These cases occurred in a public school and Dukes, hav ing been convinced that a "Fourth Disease" existed, and believing that the cases in question were of this nature, isolated the patients for only fourteen days. :Notwithstanding the short period of isolation there were no infections in the families of the children. Dukes relates another epi demic also in a school where thirty-one typical scarlet fever cases were mixed with cases of the "Fourth Disease." The incubation period of the latter was from fourteen to fifteen days whilst that of the scarlet fever cases was but two or three days. In nine cases the patients had first the "Fourth Disease" and then scarlet fever and one patient had scarlet fever first and the "Fourth Disease" later. There were two fatal cases of scarlet fever in this epidemic. Dukes also observed an other pupil who had previously had scarlet fever and then the "Fourth Disease." Many of the patients who had the "Fourth Disease" had previously been attacked by rubella. In a third house-epidemic there were nineteen cases of "Fourth Disease" and 42 per cent. of these patients had previously had rubella.
Owing to Dukes' observations covering years of experience the author considers the "Fourth Disease" as a distinct affection quite inde pendent of measles and scarlet fever. The following account is based largely on Dukes' publications.
Except for trifling pain in the throat the so-called prodromal symptoms arc wanting in most cases, although occasionally there may be a chill and several hours of nausea, headache, backache and loss of appetite. The incubation period varies from nine to twenty-one days resembling rubella and differing markedly from scarlet fever. The erup tion is usually the first indication of the disease and it may cover half of the body in a few hours. The eruption is small and thickly set. pale.
red and scarcely raised above the surface. This exanthem is also seen on the face but according to Dukes less clearly and not at all on the nose or region of the lips. The pharynx is somewhat swollen and markedly congested. The tongue is coated but the typical scarlet fever tongue is not present. The lymph-nodes of the neck are swollen, hard and about the size of a pea and they do not attain the size of the nodes in rubella. In some cases the axillary and inguinal nodes are enlarged. The eruption fades quickly and is followed by a mild but recognizable desquamation which is complete in about two weeks. Exceptionally the desquamation may be very marked. Nephritis is a rare sequel; but a trifling, rapidly disappearing albuminuria may be observed.
There are few general symptoms and the pulse rate is unaffected in the mild cases whilst it varies with the temperature in the more severe ones. The temperature ranges from 37° C. to 40° C. (98.4° F. to 104° F.). Any symptoms that are present disappear when the rash fades. The infectiousness is trifling at the onset and disappears entirely in two or three weeks. The patient is ready to get out of bed in 15 or 16 days; the isolation may be ended in two or three weeks.
I have described the " Fourth Disease" according to the author's account of it and noted how closely it resembles abortive scarlet fever. But, as we have seen, the characteristics of the "Fourth Disease" are its mild course, the absence of complications and sequels', the rapid disappearance of the infectiousness and, what I consider of especial importance, the long incubation period.
Dukes' article started a rather lively discussion amongst English and American authors and whilst part of them (W. II. Broadbent, Th. Johnstone, .T. J. Weaver, A. Croick, A. I.,. Millard and Walter Kidd) agreed with Dukes, others (C. K. Millard, A. Rutter, F. F. Caiger, F. J. Poynton. William Watson, J. W. Washburn, Ker, F. C. Curtis. II. L. K. Shaw) thought Dukes' conclusions erroneous and that eases of the "Fourth Disease" should be classed as either scarlet fever or rubella.