Site of early skin lesions in children with leprosy

Bull. Org. mond. Sante 1973, 489 107-111Bull. Wid Hith Org. Site of early skin lesions in children with leprosy L. M. BECHELLI,1 P. GALLEGO GARBAJOSA,2 MG MG GYI,3 V. MARTINEZ DOMINGUEZ,4 & R. QUAGLIATO' Most of the data on the site of early skin lesions in leprosy were obtained from the case histories of registered patients, mainly those in leprosy institutions and who had had the disease for one or more years. Such information should be treated with reservation. The purpose of this study was to determine, in a highly endemic area, the site of early skin lesions in 28 220 children who, after screening, were kept under close surveillance and re-examined yearly. In 469 patients with a single lesion, this was most often located on the thighs or buttocks, followed by the arms, forearms, legs, and lumbar region. This finding is of interest mainly for diagnostic purposes. The predilection of single early lesions for certain regions of the body does not appear to depend on whether these parts are exposed or not. The aim of this study was to determine the most usual site of early skin lesions in children with lep- rosy. This can best be done in children who are household contacts or at high risk, and who are closely followed up and examined periodically. Infor- mation obtained from the case histories of registered patients, especially those who are in leprosy institu- tions and have had the disease for one or more years, should be treated with reservation. The main purpose of studying the site of early lesions has been to facilitate diagnosis. In addition, it has stimulated discussion on the portal of entry of Mycobacterium leprae and on the initial lesion of the disease, which has been termed " leprous chan- cre" since the 18th century. REVEW OF THE LITERATURE Many leprologists have reported that early skin lesions most often occur on uncovered parts of the body (Rogers & Muir, 1946; Hernando & Alomia, 1934; Lara & de Vera, 1935; Plantilla, 1936; and 1 Professor of Dermatology, University of Sao Paulo, Brazil (formerly Chief Medical Officer, Leprosy, World Health Organization, Geneva, Switzerland). Requests for reprints should be sent to 87 Avenida Sumar6, 14100 Ribeirao Preto, Estado de Sao Paulo, Brazil. 'Team Leader, WHO Leprosy BCG Trial, Burma. National Counterpart Team Leader, Leprosy Team, Mandalay, Burma. ' Formerly Medical Officer, Leprosy, World Health Organization, Geneva, Switzerland. ' Consultant and independent observer, WHO Leprosy BCG Trial, Burma. Ehlers, quoted by Jeanselme, 1934). In countries where most people go barefoot, the first manifesta- tions of the disease have often been observed in the lower limbs, although Camargo & Bechelli (1938) failed to show such a correlation. Apart from their predilection for the face and extremities, however, early lesions are often seen on the buttocks, back, and abdomen, which in most societies are kept covered. Lara (1966) found that, in a large number of children who had been highly exposed to leprosy infection since birth, and who had been followed up closely and examined several times a year, the cheeks, extremities, and buttocks were frequently the sites of the first or early lesions, as also-despite their limited area-the elbows and knees. It is possible that, in some cases, the first lesion observed may be the " leprous chancre " developing at the point of entry of M. leprae into the skin or mucosa (Rotberg & Bechelli, 1950), and this was probably true in the case of the accidental inocu- lation reported by Marchoux (1934) and in two cases following tattooing (Porritt & Olsen, 1947). MATERIAL AND METHODS The study was carried out in an area of Burma (Singu township and part of Shwebo district) where leprosy is highly endemic (prevalence: over 30 per 1 000), in connexion with a WHO trial to determine the effect of BCG vaccination against leprosy. In total, 28 220 children were screened before being allocated to either the BCG group or the control 2986 -107- L. M. BECHELLI ET AL. group. As the children were examined every year, any lesions that developed were detected at the most 12 months after onset. Details about the clinical and bacteriological examinations and clinical tests were reported by Bechelli et al. (1970). From August 1964, when the BCG trial began, up to the end of June 1971, 610 cases had been diag- nosed among the study population. FINDINGS The sites of early skin lesions are indicated in Table 1. Only the 469 cases with a single skin lesion were considered. These lesions were most often located on the lower limbs (51.6%) and upper limbs (33 %), far less often on the trunk (12.6 %), and rarely on the face (2.1 %) and neck (0.4%). The thighs (19.4 %) and buttocks (18.3 %) were on the whole the most common sites of single skin lesions, followed by the arms (13.2 %), forearms (11.5%), legs (8.3 %), and lumbar region (5.3 .). Early lesions also occurred on almost any other area of the skin surface, although only rarely. The proportion of cases with early lesions on the knees (3.8%) and elbows (2.8Y) was relatively high con- sidering the limited extent of these areas. The distribution of single lesions on the anterior and posterior surfaces of the body is shown in Table 2, and Table 3 indicates the distribution of such lesions on the left and right sides of the body. It is noteworthy that lesions on the posterior sur- face of the elbows were relatively frequent on the right side of the body (11 cases), but that, in the study population, hardly any were seen on the left side. On the other hand, on the posterior surface of the arms, lesions were more common on the left side (29) than on the right (11). In the other regions of the body, the distribution was similar. The number of cases with only 2 or 3 lesions was small (53) and the pattern of distribution of the lesions tended to be similar to that for the 469 cases with a single lesion. The thighs, buttocks, and legs were the most frequent site, and the total numbers of lesions on the posterior and anterior surfaces of the body were similar. For obvious reasons, cases with 4 or more lesions (23) were not included in the study. In order to complete this picture of the findings in cases of leprosy diagnosed early, it may be added that 65 patients (10.6% of the 610 cases detected) presented only neural lesions. Their distribution according to the nerves affected is shown in Table 4. Table 1. Site of early skin lesions in 469 cases with a single lesion Site of lesion No. % lower limbs thighs buttocks legs knees feet 91 19.4 86 18.3 39 8.3 18 3.8 8 1.7 242 51.6 upper limbs arms forearms elbows deltoid region hands wrists 62 13.2 54 11.5 13 2.8 12 2.6 8 1.7 6 1.3 155 33.0 trunk lumbar region & lumbar vertebrae infrascapular region & dorsal vertebrae scapular region mammary region sacral region hypogastric region inframammary region sternal region epigastric region 25 5.3 12 2.6 7 1.5 6 1.3 3 0.6 3 0.6 2 0.4 1 0.2 1 0.2 60 12.6 face buccal region frontal region orbital region mental region 7 1.5 1 0.2 1 0.2 1 0.2 10 2.1 neck occipital region 2 0.4 The 610 cases found were classified as follows: indeterminate, 24.1%; indeterminate, possibly pro- gressing to the tuberculoid type, 11 %; tuberculoid, 62.4%; and tuberculoid in reaction, 2.5% (these patients usually had more than one lesion). 108 LEPROSY IN CHILDREN Table 2. Distribution of single lesions on the anterior Table 3. Distribution of single early lesions on the left and posterior surfaces of the body and right sides of the body Anterior surface Posterior surface Area No. Area No. face 10 neck 2 trunk 13 trunk 47 deltoid region 5 deltoidregion 7 arms 22 arms 40 elbows 2 elbows 11 upper limbs forearms 28 forearms 26 wrists 3 wrists 3 hands 2 hands 6 buttocks 78 thighs 50 thighs 41 knees 16 knees 2 lower limbs legs 30 legs 9 feet 7 feet I Table 4. Distribution of cases with absence of dermatological lesions Left Right Median face 4 5 1 neck 1 - 1 trunk 24 26 10 upper limbs 87 68 lower limbs 121 121 total 237 220 12 DISCUSSION From the findings, it appears that skin lesions were seen in most (89.4%) of the cases diagnosed early. Certain patients (10.6%) presented nerve enlarge- ment only. In 60 other cases, some enlargement of nerves, affecting superficial nerves in a few instances, was observed. enlarged nerves, according to the presence or Without With Enlarged nerve(s) dermatological dermatological lesions lesions right ulnar 14 9 left ulnar 10 12 both ulnar nerves 2 1 total 26 22 right lateral popliteal 22 8 left lateral popliteal 16 12 both lateral popliteal nerves 1 2 total 39 22 both ulnar and lateral popliteal nerves 0 11 a superficial nerves 0 3 right lateral popliteal and left ulnar 0 1 right radial and right ulnar 0 1 all groups 65 60 a There was temporary positivity in 10 of these cases. 109 L. M. BECHELLI ET AL. The findings with regard to the site of early skin lesions are comparable especially with those of Lara (1966) in the Philippines, who also investigated exposed children kept under close surveillance and examined repeatedly. In both studies, the buttocks were frequently the site of early lesions. However, in the Burmese children investigated in the present study, the cheeks were rarely affected. There was a greater tendency for the face to be affected when the patients had more than one lesion. It was found, both in the Philippines and in Burma, that single early skin lesions may appear in almost any region of the body, with a predilection for certain sites. Another point investigated in Burma was the localization of lesions on covered or uncovered areas of the skin. After the age of about 5 years, Burmese children wear laungyi-garments that leave only the face, forearms, elbows, hands, and feet uncovered. Most children do not go barefoot but wear open sandals. The fact that the arms and legs are among the commonest sites of single early lesions does not, therefore, appear to depend on the expo- sure of these parts of the body. CONCLUSIONS (1) Single early skin lesions in a group of children with leprosy could be found in almost any region of the body but showed a predilection for certain parts: the thighs and buttocks, followed by the arms, forearms, legs, and lumbar region. If the limited area of the knees and elbows is taken into account, the proportion of lesions occurring at those sites was relatively high. (2) Single early lesions are more common on the posterior surface of the trunk and upper limbs, and on the anterior surface of the lower limbs (excluding the buttocks). (3) The distribution of these lesions on the left and right sides of the body is approximately the same, although they occur more frequently on the right posterior surface of the elbows than on the left. (4) If children exposed to the risk of leprosy are kept under close surveillance and examined repeat- edly, most of the cases that arise among them will be detected at a stage when there is still only a single skin lesion. (5) Taking into account the distribution of single early lesions and the sites where they tend to occur; the rarity of a break in the continuity of the skin in these areas; and the fact that these parts of the body are generally kept covered or do not usually come into contact with the ulcerated lesions of infec- tious patients, it is unlikely that most of such lesions develop at the point of entry of M. leprae. UME LOCALISATION DES LESIONS CUTANEES PRECOCES CHEZ DES ENFANTS ATTEINTS DE LtEPRE Afin de d6terminer l'endroit du corps ou apparaissent les premi6res l6sions cutan6es de la lepre, on a observe un groupe de 28 220 enfants vivant dans une region de forte endemicit6 en Birmanie. Ces enfants, qui partici- paient a l'essai OMS de prevention de la lepre par le BCG, ont et6 examines annuellement pendant 6 ans de sorte que les lesions ont ete decel6es au plus tard 12 mois apres leur apparition. Durant ces 6 annees, 610 cas de lepre ont ete diag- nostiques dont 419, porteurs d'une l6sion unique, ont 6t6 retenus pour la presente etude. Presque toutes les parties du corps ont ete le lieu d'apparition des premi6res lesions, mais celles-ci ont ete observees le plus souvent en certains endroits: cuisses (19,4% des cas), fesses (18,3 %), bras 13,2 %), avant-bras (11,5 %), jambes (8,3 %), region lom- baire (5,3 %). Les l6sions siegeaient plus frequemment sur la partie posterieure du tronc et des membres supe- rieurs et sur la partie anterieure des membres inferieurs (A l'exception des fesses). Leur r6partition etait quasi similaire sur le c6te gauche et le cote droit du corps. Si l'on consid6re la repartition des lesions pr6coces de la lepre et leurs sites de predilection, la rarete d'une solu- tion de continuite de la peau a ces endroits, et le fait que ces regions du corps sont generalement couvertes et peu expos&es A entrer en contact avec des l6sions ulcerees de malades contagieux, il semble improbable que la plu- part des lesions precoces correspondent a la porte d'entree de Mycobacterium leprae dans l'organisme. 110 LEPROSY IN CHILDREN 1II REFERENCES Bechelli, L. M. et al. (1970) Bull. Wld Hlth Org., 42, 235-281 Camargo, A. T., Jr & Bechelli, L. M. (1938) Rev. bras. Leprol., 6, special number, 35-48 Hernando, E. & Alomia, A. (1934) Mth. Bull. Bur. Hith Philipp., 14, 36 & 67 Jeanselme, E. (1934) La lepre, Paris, Doin Lara, C. B. (1966) Philipp. J. Leprosy, 1, 22-57 Lara, C. B. & de Vera, B. (1935) J. Philipp. med. Ass., 15, 115-129 & 252-267 Marchoux, E. (1934) Int. J. Leprosy, 2, 1 Plantilla, F. C. (1936) Mth. Bull. Bur. Hlth Philipp., 16, 137 Porritt, R. J. & Olsen, R. S. (1947) Amer. J. Path., 23, 805 Rogers, L. & Muir, E. (1946) In: Leprosy, 3rd ed., Bristol, Wright, p. 158 Rotberg, A. & Bechelli, L. M. (1950) In: Tratado de leprologia, 2nd ed., Rio de Janeiro, Servigo Nacional de Lepra, pp. 321-328