Sickle cell-related bone marrow complications: the utility of diffusion-weighted magnetic resonance imaging.

In sickle cell disease diffusion-weighted imaging (DWI) are helpful, costeffective, and promising techniques for differentiating bone marrow involvements. So we suggest to consider a MR diffusion panoramic study (whole-body diffusion MR) when multiple follow-up imaging is required in young patients who are at high risk for chronic radiation damage, so that alternatives to PET study may be taken into consideration.

Myositis ossificans circumscripta: a paediatric case and review of the literature.

Myositis ossificans circumscripta (MOC), characterised by non-neoplastic heterotopic bone formation in soft tissue and skeletal muscle, is rare in children. At onset, it is difficult to distinguish MOC from a musculoskeletal infection or neoplasm, particularly in absence of trauma, and a biopsy is frequently required. We describe an 11-year-old boy with MOC in his thigh. At admission, minor local trauma was referred, and clinical examination revealed a tender and painful mass in the left thigh. Hypothesising a periarticular infection, a wide-spectrum antibiotic and an anti-inflammatory drug were given. The magnetic resonance imaging revealed an enlarged mass with marked enhancement of the lesion and a central, irregular non-enhanced area due to necrosis. After incisional biopsy, the histopathological examination found immature osteoblasts inside striated muscle fibres, as well as proliferating fibroblasts, which are all compatible with MOC, thereby ruling out infection or malignancy. The CT scan showed calcified deposits arranged in a ring, thus confirming MOC; a radiological follow-up was suggested to detect the lesion's maturation. Three months after diagnosis, surgical excision was performed. The post-operative period was uneventful. Six months later, the child was in good condition, with no signs of recurrence. In the literature, 57 paediatric cases have been described; most of these had an acute course, required excision and then had a favourable evolution. Our case study confirms the good prognosis of MOC and underlines how this benign condition should be considered in children presenting a tender and painful soft-tissue swelling.

Henoch Schonlein purpura in childhood: epidemiological and clinical analysis of 150 cases over a 5-year period and review of literature.

OBJECTIVE: To examine epidemiological, clinical, and outcome in Italian children affected with Henoch Schönlein purpura (HSP). METHODS: Retrospective study of children discharged with a diagnosis of HSP from the Meyer Children's Hospital, between 1998 and 2002. Epidemiological, clinical, laboratory data, treatment, and outcome were collected by reviewing medical charts. One year after data collection, the children's parents were interviewed by telephone about the outcome. RESULTS: 150 children entered the study: M:F=1.8:1; mean age 6.1+/-2.7 years. At onset, purpura was present in all cases, arthritis/arthralgias in 74%, abdominal involvement in 51%, scrotal edema in 13%, renal involvement in 54%, severe nephropathy in 7%, acute renal insufficiency in 2%, and intussusception in 0.6%. Purpura was the presenting symptom in 74%, arthritis in 15%, and abdominal pain in 12%. The most frequent laboratory abnormalities were high-erythrocyte sedimentation rate (ESR) (57%), hyper-IgA (37%), and proteinuria (42%). All patients recovered within 2 months. Recurrences, verified in 35%, were correlated with high ESR values and corticosteroid (CS) treatment, independently from other variables. After a mean 2.5-years follow-up, 2 patients had hematuria with normal renal function. CONCLUSION: Epidemiological and clinical findings in our cohort are similar to those in the literature, even though the mean disease duration was shorter than previously reported. Relapses occurred significantly more frequently in children treated with CS. This finding supports the recommendation to limit the use of steroids to a carefully selected group of HSP children. The prognosis was excellent; although severe nephropathy was found in a small percentage of the children, at follow-up all had normal renal function. Thus, our study confirms the benignity of HSP in Italian children, especially regarding renal outcome.

Comparison of the effect of antibiotic treatment on the possibility of diagnosing invasive pneumococcal disease by culture or molecular methods: a prospective, observational study of children and adolescents with proven pneumococcal infection.

BACKGROUND: Detection of Streptococcus pneumoniae in culture specimens in invasive pneumococcal disease (IPD) may be hampered by antibiotic treatment administered before hospital admission. Realtime polymerase chain reaction (RT-PCR) assays do not require viable bacteria and are therefore less influenced by antimicrobial therapy. It is not known how long results of culture or molecular tests remain positive after antibiotic therapy is begun. OBJECTIVE: The goal of the current study was to assess, in a pediatric population with a diagnosis of IPD confirmed by laboratory tests (culture and/or RT-PCR assay), the relationship between use of antibiotic therapy before hospital admission and the result of diagnostic methods (culture or molecular techniques) after admission. METHODS: This prospective, observational study was conducted from April 2006 through March 2009. All children and adolescents aged 0 to 16 years, admitted to the hospital with a diagnosis of IPD confirmed by culture and/or molecular methods, were included in the study. Previous antibiotic treatment (drug, duration of therapy) was recorded. Primers and probes designed from the pneumococcal autolysin gene (lytA) were used in an RT-PCR assay for detection of S pneumoniae. Antibiotic tolerability, permanent sequelae (after a 6-month follow-up), and deaths were recorded. RESULTS: Eighty-three patients (50 males, 33 females; 80 white, 3 Asian; mean age, 4.6 years; median age, 4.0 years; age range, 10 days-16 years) were included in the study. Fifty-four patients presented with pneumonia, 26 with meningitis/sepsis (meningitis, 19; sepsis, 7), and 3 with arthritis. Results of RT-PCR assays were positive in all 83 patients (100.0%), and 28 of the 83 patients (33.7%) also had culture-positive findings. Forty-two of the 83 patients (50.6%) had received antibiotic treatment before hospital admission, and 41 (49.4%) had not received antibiotics. Results of cultures were positive in 9 of the 42 patients with IPD (21.4%) who had received antibiotic treatment and in 19 of the 41 patients with IPD (46.3%) who had not received antibiotics (odds ratio, 3.2; 95% CI, 1.1-9.3; P = 0.03). Molecular methods appeared more sensitive than culture in any type of disease studied but particularly in patients with pneumonia, in whom the difference was statistically significant (P = 0.043). The mean length of antibiotic therapy was 1.4 days (median, 1 day; SD, 0.53 day; range, 1-2 days) for culture-confirmed cases and 4.5 days (median, 4 days; SD, 3.08 days; range, 1-15 days) for cases confirmed by RT-PCR assay (P = 0.002). No adverse reactions to the antibiotics used during home or hospital treatment were found. Two patients with meningitis suffered permanent, severe neurologic sequelae, and 1 girl died of sepsis 3 days after hospital admission. No permanent sequelae were recorded in patients with pneumonia or arthritis. CONCLUSION: In these children and adolescents with IPD, the molecular methods used appeared to be more sensitive than culture in any IPD patient, with a higher statistical significance in patients previously treated with antibiotics and in patients with pneumonia.