Steroid Responsive Atypical Hemolytic Uremic Syndrome Triggered by Influenza B Infection.

Atypical hemolytic uremic syndrome (aHUS) is characterized by uncontrolled complement activation leading to thrombotic microangiopathy and severe end-organ damage. The most common trigger for an episode of aHUS in the background of genetic deregulation of the alternative complement pathway is systemic infection. There are only 4 reported cases of aHUS triggered by influenza B thus far. Current accepted therapies for aHUS include plasma exchange and eculizumab. We describe a unique patient with aHUS with a rare membrane cofactor protein mutation triggered by influenza B infection, who achieved complete remission with treatment with high-dose corticosteroids after failure of plasmapheresis.

Osteosarcoma Metastases With Direct Cardiac Invasion: A Case Report and Review of the Pediatric Literature.

Metastatic osteosarcoma with direct cardiac involvement is an exceptionally rare finding, with only 63 total reported cases in the English literature over the past 123 years. Although the precise incidence is unknown, we estimate that direct cardiac involvement currently occurs in <2% of metastatic osteosarcoma cases. We also find that before the adoption of adjuvant chemotherapy as a standard of care therapy for osteosarcoma, metastatic osteosarcoma to the heart was much more common than it is today, as cardiac involvement occurred in ∼20% of cases of metastatic osteosarcoma before the 1980s. This suggests that adjuvant chemotherapy has not only improved the overall prognosis of osteosarcoma, but also altered the metastatic pattern of disease. In this paper we present the case of an 11-year-old boy with metastatic osteosarcoma to the cardiac interventricular septum, as well as review 20 other previously reported pediatric cases of metastatic osteosarcoma to the heart. We also analyzed the cardiac surgical outcomes for 11 pediatric patients with metastatic osteosarcoma to the heart. The median disease-free survival time was 12 months, demonstrating that metastatic osteosarcoma to the heart is currently a rare occurrence with a poor prognosis.

The Clinical Significance of Initial Pulmonary Micronodules in Young Sarcoma Patients.

BACKGROUND: The clinical significance of subcentimeter nodules identified on staging chest computed tomography (CT) for sarcoma remains unknown. Our goal was to evaluate the effect of initial pulmonary nodule size and number on survival rates in young, newly diagnosed sarcoma patients. METHODS: Medical records were reviewed for all patients ≤50 years of age with primary, high-grade bone or soft tissue sarcoma at our institution over a 10-year period. This population was divided into patients with no nodules (group 1); 1 nodule <5 mm (group 2);>1 nodule <5 mm (group 3); and ≥1 nodule ≥5 mm (group 4). Kaplan-Meier analyses with log rank tests were performed to compare overall and disease-free survival between these 4 groups, as well as between patients with unilateral and bilateral nodules. RESULTS: There were 74 patients in group 1 (59.2%), 26 in group 2 (21%), 11 in group 3 (9%), and 13 in group 4 (10%). Mean follow-up was 74 (range, 6 to 191 mo) months. Survival was only slightly worse with larger nodules but significantly worse with multiple nodules. In addition, patients with bilateral nodules had a significantly worse prognosis than those with multiple unilateral nodules. CONCLUSIONS: These data suggest that in young patients with high-grade sarcoma, the number and distribution of subcentimeter pulmonary nodules are an important prognostic factor, whereas nodule size may be less relevant.