On the first day of life, a male infant born at 36 weeks’ gestation (weight 2,520 g, height 46 cm), with an antenatal diagnosis of Down’s syndrome and atrioventricular duct defect, showed hepatomegaly, splenomegaly, bradycardia and sleep apnoea. On day 1, his white blood cell count was high (50,100/mm3; normal range 10,000–26,000/mm3, with 14% polynuclear neutrophils, 20% lymphocytes, 1% monocytes and 65% blast cells), with 377,000/mm3 platelets. Immunophenotyping of peripheral blood showed a myeloblastic leukaemia profile (CD33+, CD117+, CD71+, CD7+, CD4+ and partially CD41a), and bone marrow aspiration findings revealed 54% blast cells with no megakaryocytes. At age 1 week, the infant began to develop erythematous vesicles and pustular lesions on his face (Fig. 1A), with some on his trunk and bottom (Fig. 1B). These lesions rapidly became crusty and oozing. Laboratory results found no antinuclear, anti-basal membrane or anti-intercellular substance antibodies. Bacterial, viral and fungal cultures of the pustules were negative. Histopathology of 2 cutaneous biopsies, including immunostainings for CD34, CD68P, CD45, CD1a, C-KIT and D2-40, showed polymorphous dermal inflammation and no blast cells. Topical and systemic antibiotics (mupirocin and cefazolin, respectively) for 10 days did not induce improvement.
Fig. 1.
Pustules and crusts on (A) the face and (B) gluteal area.
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