Subcutaneous fat necrosis of the newborn (SFN) is a rare form of panniculitis that can be complicated by hypercalcemia and nephrocalcinosis. We conducted a 20-year retrospective cohort study of 30 patients to describe the clinical characteristics of SFN and the prevalence of hypercalcemia and other complications. Hypoxia and therapeutic hypothermia (TH) seem to play an important role in the development of SFN. Hypercalcemia developed in 63% of patients, three of whom developed nephrocalcinosis. There is a need for well-controlled prospective studies to determine the natural history, prevalence, and incidence of complications of SFN.

Background. Skin diseases among pediatric patients differ from those in adults. Epidemiological studies are scarce, and those performed in Mexican population date back thirty years. It is likely that these diseases might have changed their frequency. Material and Methods. Retrospective study in first-time patients referred to a pediatric dermatology service between January 1994 and December 2003. Demographics and diagnosis were recorded and compared with the results of a previous study performed in the same institution. Results. We included 5250 patients (52.55% female, 47.47% male) with 6029 diagnoses. The most frequent dermatoses found were atopic dermatitis (14.59%), viral warts (6.62%), acne (5.53%), pityriasis alba (3.98%), melanocytic nevi (3.85%), xerosis (3.57%), keratosis pilaris (3.19%), seborrheic dermatitis (2.37%), hemangioma (2.26%), and papular urticaria (2.24%). Most dermatoses increased their frequency when compared to the previous study. Conclusion. The frequency of pediatric dermatoses in our institution has changed in the last two decades. Environmental and sociocultural factors and institutional policies might account for these results.

The LTA is potentially a valuable diagnostic tool for DHS; however, its sensitivity, specificity, NPV, and PPV seem to vary according to the drug involved in the reaction.

Background Serum sickness-like reaction (SSLR) is an acute inflammatory condition affecting predominantly children. The pathophysiology remains unclear, but drugs are considered the main trigger. Objective The aim of this study was to describe the clinical and laboratory features, triggers, and treatment modalities in children diagnosed with SSLR. Methods We conducted a 10-year retrospective cohort study including all paediatric patients (0 to 18 years old) with query SSLR referred to the Adverse Drug Reactions Clinic at the Children’s Hospital of Western Ontario. Diagnostic criteria included acute skin rash plus joint inflammation with or without fever. Results We included 83 patients (47 females). Age ranged from 11 months to 12 years (mean 3.2 years). Amoxicillin was the trigger in 82.7% of patients. The mean time between the exposure to the triggering drug and the development of the symptoms was 8.5 days. Urticaria-like and Erythema multiforme-like lesions were present in 35% and 38.5% of the cases, respectively. Joint inflammation affecting hands/feet was present in 60%. Pruritus, lip/eye swelling, and fever were reported in 33, 31, and 45% of patients, respectively. The lymphocyte toxicity assay (LTA) showed incremental T-cell toxicity in 32 of 34 patients. Children that received treatment with antihistamines/nonsteroidal anti-inflammatory drugs (NSAIDs) plus oral steroids had a mean recovery time shorter than those treated only with antihistamines/NSAIDs (6 versus 8 days; P=0.09). Conclusions In our study, SSLR was mostly triggered by amoxicillin and had a mean time presentation of 8.5 days. Further prospective and well-conducted studies are needed.