Presentation

A 13-year-old boy presented with intermittent, high-grade fever for 10 days that was associated with redness of eyes and oral mucosa, and generalized macular rash. Examination revealed oro-mucosal erythema, lip cracking, and extensive sheet-like periungual desquamation in all fingers and toes (Fig. 1a). No nail abnormalities were noted during the acute phase of illness. Laboratory investigations revealed leukocytosis (16.8 × 109 cells/L); thrombocytosis (560 × 109 cells/L); serum albumin: 30 g/L (normal: 35–55 g/L); ESR: 68 mm/h (normal: 0–15 mm/h); and CRP: 56 mg/L (< 10 mg/L). Trans-thoracic two-dimensional echocardiography showed normal coronary artery dimensions. A diagnosis of Kawasaki disease (KD) was made and intravenous immunoglobulin (IVIg) (2 g/kg) was administered over 12 h along with aspirin (30 mg/kg/day). He had defervesce of fever within 24 h of IVIg therapy following which dose of aspirin was reduced to 3 mg/kg/day. On 2 weeks of follow-up, he developed extensive onychomadesis (Fig. 1b) and paired, transverse, white lines in all fingernails. These lines were non-palpable and without any indentation, suggesting a diagnosis of Muehrcke’s lines (Fig. 1c). At 6 weeks of follow-up, Muehrcke’s lines disappeared and Beau’s lines were noted in all fingernails (Fig. 1d). The follow-up echocardiogram at 6 weeks was normal.

Fig. 1
figure 1

Cutaneous and nail changes in the adolescent boy with Kawasaki disease. a Sheet-like desquamation involving the periungual region, soles, and dorsum of both feet. b Blue arrows: onychomadesis (separation of the nail plate from the nail bed) seen in all fingers in convalescent-phase. c Black arrows: paired, transverse white lines suggestive of Muehrcke’s lines in convalescent-phase. d Arrowheads: Beau’s lines (transverse grooves on nail plate) in the same patient at 6 weeks of illness

Full size image

Discussion

A myriad of nail abnormalities has been described in KD that include Beau’s lines, chromonychia, pincer nail deformity, and leukonychia [1]. Muehrcke’s lines are paired non-palpable transverse white lines on nails that disappear on compression of nail beds. These are believed to occur secondary to abnormalities in nail vasculature during periods of metabolic stress [2]. These have previously been described in children with chronic malnutrition, hypoalbuminemia, liver disease, and cancer chemotherapy. KD has a component of vascular leakage during the acute phase which is associated with peripheral edema and hypoalbuminemia [3]. These lines are an important clinical finding in KD and these might reflect stress due to systemic inflammation or may be due to the hypoalbuminemia in KD.