Kaposiform lymphangiomatosis: a distinct aggressive lymphatic anomaly.

OBJECTIVE: To describe the clinical and imaging characteristics of a new lymphatic disorder with a unique histological pattern and poor prognosis. STUDY DESIGN: An observational, retrospective study identified and characterized 20 patients with distinct lymphatic histopathology referred to the Vascular Anomalies Center at Boston Children's Hospital between 1995 and 2011. RESULTS: The median age at onset was 6.5 years (range, birth to 44 years). Clinical and radiologic findings suggested a generalized process. The most common presentations were respiratory symptoms (50%), hemostatic abnormalities (50%), and an enlarging, palpable mass (35%). All patients had mediastinal involvement; 19 patients developed pericardial (70%) and/or pleural effusions (85%). Extrathoracic disease manifested in bone and spleen and less frequently in abdominal viscera, peritoneum, integument, and extremities. Despite aggressive procedural and medical therapies, the 5-year survival was 51% and the overall survival was 34%. Mean interval between diagnosis and death was 2.75 years (range, 1-6.5 years). CONCLUSIONS: We describe a clinicopathologically distinct lymphatic anomaly. We propose the term kaposiform lymphangiomatosis (KLA) because of characteristic clusters or sheets of spindled lymphatic endothelial cells accompanying malformed lymphatic channels. The intrathoracic component is most commonly implicated in morbidity and mortality; however, extrathoracic disease is frequent, indicating that KLA is not restricted to pulmonary lymphatics. The mortality rate of KLA is high despite aggressive multimodal therapy.

Serum biomarkers and transient elastography as predictors of advanced liver fibrosis in a United States cohort: the Boston children's hospital experience.

OBJECTIVE: To evaluate and compare the ability of serum hyaluronic acid (HA) and human cartilage glycoprotein-39 (YKL-40) values, as well as transient elastography (TE) findings, to predict advanced hepatic fibrosis in a cohort from a single pediatric center. STUDY DESIGN: Subjects who underwent liver biopsy analysis within 12 months before enrollment were eligible for this prospective study. HA and YKL-40 measurements were obtained within 1 month of TE. A METAVIR score of F3 or F4 was considered to indicate advanced fibrosis. RESULTS: A total of 128 patients (51% males) aged 1.4 months to 27.6 years (22% aged <2 years) were enrolled. Thirty-one subjects had data on only HA and YKL-40 measurements, and 97 subjects had data on both blood tests and TE. For the prediction of advanced fibrosis, the area under the receiver operating characteristic curve (AUC) values were 0.83 for TE, 0.72 for HA, and 0.52 for YKL-40. The AUC of 0.83 for TE was statistically significantly greater than the AUCs for HA (P = .03) and YKL-40 (P < .0001). Optimal cutpoints for predicting F3-F4 fibrosis were 8.6 kPa for TE (P < .0001), 43 ng/mL for HA (P < .0001), and 26.2 ng/mL for YKL-40 (P = .85). The combination of TE and HA was not better than TE alone for predicting advanced fibrosis (P = .15). CONCLUSION: In this study, which evaluated TE, HA, and YKL-40 to predict liver fibrosis in children in the US, YKL-40 had no predictive value and TE was superior to HA, but the addition of HA did not improve the performance of TE. Our data suggest that TE and HA may be useful noninvasive tools for assessing liver fibrosis in children.