A rash that’s more than skin deepBMJ 2018; 360 doi: https://doi.org/10.1136/bmj.k8 (Published 25 January 2018) Cite this as: BMJ 2018;360:k8
- Xinyi Chin, associate consultant, paediatric medicine1,
- Daisy Kwai Lin Chan, senior consultant, neonatology2,
- Jin Ho Chong, paediatric dermatology consultant1
- 1KK Women’s and Children’s Hospital, Singapore
- 2Singapore General Hospital, Singapore
- Correspondence to Xinyi Chin
A 6 week old baby presented with petechiae and erythematous macules over the periorbital and perioral areas, spreading to the forehead and malar areas (fig 1). She had been delivered vaginally at 36 weeks’ gestation and was small for gestational age, with no hepatosplenomegaly. Serology tests for toxoplasma, rubella, cytomegalovirus, and herpes simplex were negative. The baby had transient neonatal thrombocytopenia secondary to maternal chronic immune mediated thrombocytopenia (also known as immune thrombocytopenic purpura).
Given the distribution of the rash and the mother’s history of immune thrombocytopenia, an auto-antibody profile was performed. This showed positive speckled antinuclear antibodies titre >1/800 (normal range <1/100), positive anti-double stranded DNA antibody levels 65.11 IU (<25 IU), and presence of extractable nuclear antigen antibodies anti Ro/SSA, La/SSB, Sm, RNP, Scl70, and Jo-1, with index values of 5.8, 6.1, 5.2, 4.8, 4.0, and 4.7, respectively (<1.0). Complement levels were C3 0.42 g/L (0.51–1.60 g/L) and C4 <0.03 g/L (0.07–0.30 g/L). Full blood count showed a haemoglobin level of 8.7 g/dL (9.0-14.0 g/dL), total white blood cell count 10.74×109/L (5.00-15.00×109/L) and platelet count 144×109/L (150-450×109/L). Liver and renal function tests were normal. The child was well, and the lesions resolved by the time she was 6 months old (fig 2).
1. What are the differential diagnoses of the rash?
2. What is the likely diagnosis?
3. What is the suggested …