Cervical mycobacterial infection

THE pattern of mycobacterial infection has changed in recent years, the incidence of the pulmonary form having decreased, whilst the extrapulmonary has not shown a similar tendency (Llewelyn and Dorman, 1971; Newcombe, 1971; Hooper, 1972). Whilst laryngeal (Maran and Stewart, 1971) and aural (Palva et al., 1973) tuberculosis are by no means rarities, the most common form of mycobacterial infection encountered in otolaryngological practice presents as a cervical adenitis (Toremalm and Wihl, 1968). Recent publications have indicated that the incidence of the latter may be increasing (Newcombe, 1971; Ord and Matz, 1974; Wong and Jafek, 1974). Kent (1967) regarded tuberculous cervical lymphadenitis as a local manifestation of a systemic infection, but a striking feature of many reports in the literature is the infrequent occurrence of systemic, and especially pulmonary, involvement (Wilmot et al., 1957; Black and Chapman, 1964; Newcombe, 1971; Ord and Matz, 1974; Wong and Jafek, 1974). It ha been recognized for centuries that tuberculous cervical lymphadenitis, or scrofula, had often a benign course, and spontaneous resolution may have accounted for the apparent efficacy of the king's touch. A possible explanation is that at least some of the cases of scrofula may have been due to an unrecognized infection with atypical mycobacteria. Human tuberculosis is due to infection either with Mycobacterium tuberculosis or M. bovis. It has been known since the turn of the century that other forms of mycobacteria are to be found widely distributed in nature, but these were for a long time regarded as non-pathogenic for humans. Following the introduction of effective anti-tuberculous chemotherapy, it became apparent that forms of mycobacteria other than M. tuberculosis and M. bovis were occasionally recoverable from patients with diseases similar to tuberculosis. These organisms have been termed atypical, or anonymous, mycobacteria, and have been classified according to their bacteriological growth characteristics into the following four groups: group 1, photochromogens; group II, scotochromogens; group III, non-photochromogens, and group IV, rapid growers (Runyon, 1959). The first descriptions of cervical lymphadenitis due to atypical mycobacterial infection appeared in 1956 (Prissick and Masson, 1956; Weed