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Features Departments Information |
 Rebecca Cummins, MD
Amy S. Paller, MD
Annette Wagner, MD
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Dermatology quiz ROBERT SIDBURY, MD aSpring 2000  A TWO-MONTH-OLD BOY was referred to the dermatology clinic for evaluation of a rash. The rash began on his face at one week of age and subsequently spread to his scalp, trunk, and upper extremities. No improvement was noted with application of a mild topical steroid cream. The patient’s past medical history was unremarkable. He was born full-term via spontaneous vaginal delivery and weighed 6 lbs 2 oz at birth. He was on no medications. His family history was significant for a mother with ichthyosis vulgaris. The patient had no known exposure to any infectious diseases.  On physical examination the infant appeared happy and well-nourished. His cardiac exam revealed a normal rate and rhythm. He had no appreciable hepatosplenomegaly or lymphadenopathy. Skin examination showed several annular and serpiginous erythematous scaling plaques on his face, scalp and trunk with less involvement on the upper extremities. The orbital areas were surrounded by a pink discoloration (Figures 1 and 2). The most likely diagnosis is:
Associated findings can include:
Answers: C and E, respectively. A biopsy of one of the skin lesions revealed interface dermatitis. Laboratory testing of the patient revealed a normal CBC, an elevated ANA of 1:320 (normal, <1:80), a positive SSB/La but a negative SSA/Ro. Blood work on the patient's mother revealed mild leukopenia with a WBC of 3.2 (normal, 3.5–10.5) K/uL. Hemoglobin and platelet counts were within normal limits. An ANA was elevated at 1:2560 with a speckled pattern. She had a positive SSB/La but negative SSA/Ro, anti-Smith, anti-RNP, and dsDNA autoantibodies. Cardiolipin IgG was elevated at 41(<15) but cardiolipin IgM was undetectable, as was lupus anticoagulant. The patient was diagnosed with neonatal lupus. He was referred for an echocardiogram and his mother was referred to rheumatology for evaluation of a possible connective tissue disease. Neonatal lupus is an autoimmune disease of the newborn with a characteristic cutaneous eruption and risk of other organ involvement, including cardiac, hepatic, and hematologic. The manifestations of the disease are secondary to the presence of maternal autoantibodies which pass transplacentally to the developing fetus. Most mothers of infants with neonatal lupus have antibodies directed against Ro and La antigens and less commonly, the circulating antibodies are directed against U1RNP. 1,2 The cutaneous manifestations of neonatal lupus usually appear within the first few weeks of life. The lesions are typically erythematous annular or polycyclic plaques with a propensity to involve the face and scalp due to the photosensitive nature of the eruption. Lesions of discoid lupus erythematosus, atrophoderma, or telangiectasias may also be seen. Biopsy of the rash reveals changes consistent with subacute cutaneous lupus erythematosus, and direct immunofluorescence reveals particulate linear IgG at the basement membrane. Resolution can be anticipated by 6 to 8 months of age coincident with clearance of maternal autoantibodies from the infant's circulation. No treatment is usually necessary and the lesions typically heal without scarring.3 Cardiac involvement in neonatal lupus is responsible for the major morbidity and mortality associated with this disease. Affected patients typically present with complete or partial congenital heart block detected in utero or within the first few months of life. The mortality rate is indirectly related to gestational age at birth with 52% of infants born before 34 weeks of gestation not surviving in one study. That rate markedly diminished in those infants born at a later gestational age. Of the surviving infants, a high percentage will require pacemaker placement.4 Unlike cardiac involvement which is irreversible, other organ involvement in neonatal lupus tends to be transient and less severe. Hepatic involvement typically presents with hepatomegaly and elevated liver transaminases, consistent with cholestasis. The most common hematologic abnormality is thrombocytopenia, although patients may also display hemolytic anemia and leukopenia.1,2 The minority of mothers of babies with neonatal lupus have collagen vascular disorders at the time when their babies are diagnosed, particularly systemic lupus erythematosus, Sjögren’s syndrome, or an undifferentiated connective tissue disease. Most of the mothers are asymptomatic. These asymptomatic women have a low but increased risk of developing a rheumatic disorder with time and should be referred to a rheumatologist or internist for a thorough evaluation and close follow up. All women with an infant with neonatal lupus must also be carefully screened by their obstetricians during future pregnancies as successive siblings have an increased risk of manifesting neonatal lupus as well.5 The long term rheumatologic outcome of babies with neonatal lupus is good. Their history of having had neonatal lupus does not put them at increased risk of developing a connective tissue disease in the future. Instead their risk relates to their genetic predisposition based on their family history.5 REFERENCES 1. Tseng CE, Buyon JP: Neonatal lupus syndrome. Rheum Dis Clin North Am 1997;23(1):31–54. 2. Silverman ED, Laxer RM: Neonatal lupus erythematosus. Rheum Dis Clin North Am 1997;23(3):599–618. 3. Weston WL, Morelli JG, Lee LA. The clinical spectrum of anti- Ro-positive cutaneous neonatal lupus erythematosus. J Am Acad Dermatol 1999;40:665–81. 4. Buyon JP, Hiebert R, Copel J, et al: Autoimmune-associated congenital heart block: Demographics, mortality, morbidity and recurrence rates obtained from a national neonatal lupus registry. J Am Coll Cardiol 1998; 31(7):1658–66. 5. Brucato A, Franceschini F, Buyon JP: Neonatal lupus: Long term outcomes of mothers and children and recurrence rates. Clin Exp Rheumatol 1997;15:467–473. |