RT Journal A1 Sahn EE, Grine R T1 A pigmented paraspinal plaque in an infant JF Archives of Dermatology JO Archives of Dermatology YR 1995 FD May 1 VO 131 IS 5 SP 614 OP 614 DO 10.1001/archderm.1995.01690170117021 UL http://dx.doi.org/10.1001/archderm.1995.01690170117021 AB REPORT OF A CASE  A 19-month-old boy with numerous nevi, including a 10-cm congenital nevus of the scalp, developed a pigmented left paraspinal plaque at the age of 10 months. There was hypertrichosis within the plaque, and the mother reported ''bulging'' when the area was stroked. A vertebral radiograph was normal. On physical examination, there was a 3×3-cm smooth, hyperpigmented plaque with hypertrichosis at approximately Level L2-4 in the left paraspinal region. (Figure 1 and Figure 2) Magnetic resonance imaging of the lumbar spine was normal.A skin biopsy specimen was obtained from the left paraspinal plaque (Figure 3 and Figure 4).What is your diagnosis?DIAGNOSIS:  Congenital smooth-muscle hamartoma.HISTOPATHOLOGIC FINDINGS  The biopsy specimen demonstrated an unusual array of smooth-muscle bundles within the reticular dermis. These smooth-muscle bundles were well-defined and extended in various directions. Some of the smooth-muscle bundles within the reticular dermis.