|Year : 2013 | Volume
| Issue : 3 | Page : 214-216
Congenital giant melanocytic nevus with ambiguous genitalia in an 8-year-old child: A rare combination
Aliyu Ibrahim1, Abdullah Ramatu2
1 Department of Paediatrics, Aminu Kano Teaching Hospital, Bayero University, Kano, Nigeria
2 Dermatology Unit, Aminu Kano Teaching Hospital, Bayero University, Kano, Nigeria
|Date of Web Publication||14-Feb-2014|
Department of Paediatrics, Aminu Kano Teaching Hospital, Bayero University, Kano
Source of Support: None, Conflict of Interest: None
Congenital melanocytic nevi may be common, quite extensive and even benign, but a giant congenital nevus is rare and has potential for malignant transformation. Giant nevus could occur in any part of the body; though, it is most common on the trunk and may be associated with other congenital malformations such as spina bifida, meningocele. However, there is a dearth of information on its combination with ambiguous genitalia. We therefore report a case of an 8-year-old child with a giant melanocytic nevus on the face and neck with widespread satellite nevi and ambiguous genitalia.
Keywords: Ambiguous, genitalia, giant, melanocytic, nevus
|How to cite this article:|
Ibrahim A, Ramatu A. Congenital giant melanocytic nevus with ambiguous genitalia in an 8-year-old child: A rare combination. Saudi J Health Sci 2013;2:214-6
| Introduction|| |
Pigmentary skin lesions are common in children. They may be congenital or acquired and also some may be benign or have potential for malignant transformation. A giant melanocytic nevus also known as congenital bathing trunk nevus is an uncommon disease with a reported incidence of 1:500,000 newborns;  though, there are reported cases in Nigeria,  its true incidence is not known. Giant congenital melanocytic nevus commonly involves the lower trunk and lower limbs and is less common on the scalp and facial area. Involvement of the scalp and the posterior axial region may also involve the central nervous system in patients with neurocutaneous melanosis.  Giant congenital melanocytic nevus has the potential for malignant transformation, but the exact incidence of that risk is not completely known as some authors have quoted about 2.5-5%,  while others in 13.7%  of cases. Congenital melanocytic nevi may be associated with other defects such as spina bifida, meningocele, club foot and hypertrophy or atrophy of a limb affected by the nevus;  however, its association with an ambiguous genital is not clear, though once reported by Basanti et al.  this will probably be the second case report to the best of the authors knowledge. We therefore report a case of an 8-year-old child who presented with a rare combination of giant congenital melanocytic nevus with satellite nevi and ambiguous genitalia.
| Case Report|| |
An 8-year-old child presented with fever and poor appetite of 1 week duration and was treated for enteric fever. However, on closer observation this child had an extensive darkly hyperpigmented skin lesion, which had been present since birth and also had an ambiguity of the external genitalia, but was raised as a male child. The pregnancy and neonatal period was not adversely eventful and was a product of a non-consanguineous marriage. The mother was a 25-year-old stay at home mother; she never smoked cigarette or drank alcohol and never had any known chronic medical illness, there was no similar problem in the family. The child had been to several hospitals and had not gotten the desired medical attention due to lack of the necessary expertise. On physical examination, the hyperpigmented skin lesions involved the right side of the face extending to involve the neck and the upper trunk, also the posterior region of the neck was involved; the neck and the trunk lesion crossed the midline extending to the left side measuring 22 cm in its longest length [Figure 1] and [Figure 2]. Those on the cheek were elevated, velvety with an associated tuft of hairs. There were several satellite lesions on the trunk and limbs [Figure 3]. The right side of the face was hypoplastic [Figure 4] and [Figure 5]. The child also had low set ears and high arched palate with a small chin. The external genitalia was ambiguous, with no clear penile shaft or prepuce rather a clitoris-like structure with stretch length of 4 cm and a diameter of 8 mm, two pigmented thickened, rugated labioscrotal folds with [Figure 6] posterior fusion and but a palpable gonad in the right fold and gonadal mass felt in the left inguinal region. The urethral opening was ventral with a split on the ventral surface of the shaft extending from the region of the labioscrotal fold to the tip of the clitoral-like projection. The child had a normal height, weight and occipitofrontal circumference for age. The abdominal and pelvic ultrasound revealed absent uterus and its adnexal structures. Patient's karyotype was not done due to lack of that expertise in our setting; the serum levels of follicle-stimulating hormone, luteinizing hormone and testosterone were within normal range. Similarly, the serum cortisol level was normal. The skin histology report confirmed the presence of nests of melanocytes extending well into the dermis; the hemoglobin electrophoresis of the child was SS (sickle cell anemia); the serum electrolytes were normal; an intravenous urography did not reveal any other structural abnormality and also had a normal brain computed tomography scan study. A diagnosis of giant congenital melanocytic nevus with satellite nevi and grade three perineal hypospedia was made [Figure 7].
|Figure 5: Combined nevi and ambiguous genitalia; with prominence of scrotal region due to the gonad|
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| Discussion|| |
Giant congenital melanocytic nevus commonly involves the lower back and thighs,  but our patient had it on the right side of the face, neck extending to the upper trunk, which was similar to that reported by Gupta et al.  Though the posterior neck was also involved, our patient lacked any neurologic complaints and had an appropriate developmental milestone comparable with peers. The combination of a giant congenital melanocytic nevus and an ambiguous genitalia is rare, while Basanti et al.  reported giant bathing trunk nevus on the lower back and thigh, our patient had it on the face and neck region, which made it unique.
The ability to palpate gonadal mass in the labioscrotal fold well below the level of the inguinal ligament makes it likely to be a testis,  the absence of a uterus and its adnexal structures furthermore makes the patient a likely genotypic male child despite our inability to do karyotyping. The external genitalia of the index case fits the description of the third degree (perineal) hypospadias, but the supposed glans penis had no prepuce or dorsal hood at birth which made it look more like an enlarged clitoris. The association of giant melanocytic nevus with ambiguous genitalia is not clear while Basanti et al.  attributed their earlier observation to an incidental finding, this second case report calls for closer observation by clinicians, for this may represent a new clinical syndrome, which hitherto had never been reported before.
| Conclusion|| |
Giant congenital melanocytic nevus is a rare pigmentry skin disorder that may be associated with other congenital malformation such as spina bifida, meningocele, club foot and hypertrophy or atrophy of a limb involved by the nevus; however, this is rare documented case of an association of ambiguous genitalia with facial giant nevus.
| References|| |
|1.||Grichnik JM, Rhodes AR, Sober AJ. Benign neoplasias and hyperplasias of melanocytes. In: Wolff K, Goldsmith LA, Katz SI, Gilchrest BA, Paller AS, Lefell DJ, editors. Fitzpatrick′s Dermatology in General Medicine. 7 th ed. New-York city: McGraw-Hill; 2008. p. 1099-103. |
|2.||Ammed H, Pindiga UH, Onuora CU, Abimiku A, Dikko AA. Giant congenital pigmented naevus with unusual presentation and early malignant transformation in a Nigerian infant: Case report and review of the literature. Niger Postgrad Med J 2001;8:26-31. |
|3.||DeDavid M, Orlow SJ, Provost N, Marghoob AA, Rao BK, Wasti Q, et al. Neurocutaneous melanosis: Clinical features of large congenital melanocytic nevi in patients with manifest central nervous system melanosis. J Am Acad Dermatol 1996;35:529-38. |
|4.||Shah KN. The risk of melanoma and neurocutaneous melanosis associated with congenital melanocytic nevi. Semin Cutan Med Surg 2010;29:159-64. |
|5.||Russell JL, Reyes RG. Giant pigmented nevi. J Am Med Assoc 1959;171:2083-6. |
|6.||Mackie RM. Disorders of the cutaneous melanocyte. In: Burns T, Breathnach S, Cox N, Griffiths C, editors. Rook′s Textbook of Dermatology. 7 th ed. Oxford: Blackwell Science; 2004. p. 38-9. |
|7.||Basanti D, Prasenjeet M, Nibedita P, Maitreyee P, Basanta S. Congenital bathing trunk nevus with ambiguous genitalia: A rare coincidence. Indian J Dermatol 2009;54:298-9. |
|8.||Mackie RM. Melanocytic naevi and malignant melanoma. In: Champion RH, Burton JL, Burns DA, Breathnach SM, editors. Textbook of Dermatology. 6 th ed. Oxford: Blackwell Scientific Publications; 1998. p. 1717-52. |
|9.||Gupta RR, Puri KJ, Sahani SS. Giant hairy ′bathing trunk′ naevus with multiple congenital melanocytic naevi. Indian J Dermatol Venereol Leprol 2002;68:344. |
|10.||Davidoff F, Federman DD. Mixed gonadal dysgenesis. Pediatrics 1973;52:725-42. |
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7]