Sonographic Evaluation of Acute Osteomyelitis in Infants

PURPOSE: To analyze the related sonographic findings and to determine the value of sonography in establishing the diagnosis of acute osteomyelitis in infants. MATERIALS AND METHODS: The sonographic findings of eleven infants aged 10 days-4 months (mean, 45 days) with acute osteomyelitis were retrospectively evaluated. The involved bones were the femur (n=5), humerus (n=2), tibia (n=2), rib(n=1), sternum(n=1), and calcaneus(n=1). Discontinuity or destruction of cortical margins, echotexture of the metaphysis and epiphysis, the presence of subperiosteal hypoechoic lesion, adjacent soft tissue swelling, distension of the joint capsule, the echotexture of joint effusion, and dislocation or subluxation of the involved joint were evaluated. The sonographic findings were compared with the plain radiographic (n=12) and MR (n=5) findings, with special attention to the identification of the metaphyseal or epiphyseal bony lesions and the involvement of adjacent joints. RESULTS: The sonographic findings of osteomyelitis were cortical discontinuity or destruction (n=12), hypoechoic lesions with an echogenic rim in the metaphysis (n=12), subperiosteal hypoechoic lesions (n=8), soft tissue swelling (n=9), a distended hip joint, with echogenic fluid (n=5), ill-demarcated echogenic lesions in the capital femoral epiphysis (n=5), and a subluxated hip joint (n=3). Plain radiographs revealed well or ill-defined osteolytic lesions in the metaphysis, accompanied by cortical destruction (n=8), new periosteal bone formation (n=3) and reactive sclerosis (n=2). Abnormality of the femoral epiphyses and joint involvement were not detected on plain radiographs, and in four cases no abnormality was noted. MR imaging showed that at T1WI, affected bony lesions were of low signal intensity and enhanced, with high signal intensity at T2WI. In all cases, both metaphyseal and epiphyseal lesions were demonstrated at MRI, but in one of the three cases in which an epiphyseal lesion was seen at MRI, this was not detected at US. CONCLUSION: Sonography is not only more sensitive than radiography in evaluating metaphyseal bony lesions but also useful in assessing concomitant joint and epiphyseal involvement of acute osteomyelitis in infants. Sonography is, therefore, a useful additional diagnostic tool for the early detection and management of acute osteomyelitis in infants.

Rib Enlargement in Premature Infants with Bronchopulmonary Dysp lasia

PURPOSE: The purpose of this study is to describe the rib changes seen in patients with bronchopulmonary dysplasia (BPD). MATERIALS AND METHODS: Serial chest radiographs of nine premature infants with BPD who showed diffuse rib enlargement were reviewed for hyperinflation, which was compared with the observed degree of rib enlargement. Vibrator chest physiotherapy was performed in all cases, and five infants underwent conventional ventilation plus high frequency oscillatory ventilation therapy. Their calcium level was normal where-as alkaline phosphatase and phosphate levels were high. In all infants except one, liver enzyme levels were normal. For the treatment of patent ductus arteriosus, infection, and BPD, medications including indomethacin, antibiotics, and examethasone were administered. Vitamin D was given to all patients with total parenteral nutrition. RESULTS: Rib enlargement was found to be severe (n=4), moderate (n=3), or mild (n=2) with undulating margins or posterior tapering (n=2). Hyperinflation was noted in eight patients, in seven of whom it was moderate to seve r e. Among these seven, rib enlargement was severe (n=2), moderate (n=3), or mild (n=2). In one infant with mild hyperinflation, rib enlargement was seve r e. Bilateral irregular infiltrates and at-electases were noted in all patients. CONCLUSION: In BPD patients, rib enlargement may be seen. In order to differentiate this process from systemic bone disease or bony dysplasia, an awareness of the rib changes occurring in patients with BPD may be important.

MR Imaging of Fukuyama Congenital Muscular Dystrophy: A Case Report

Fukuyama congenital muscular dystrophy is a genetic disease and common in Japan. The typical clinical features are hypotonia with an early infantile onset and severe developmental delay. The diagnosis is based on pathologic evidence of muscular dystrophy revealed by biopsy or an increased serum creatine kinase levels. Involvement of the brain is characterized by abnormal cerebral cortical dysplasia, cerebellar dysplasia, and white matter changes. We encountered a case of Fukuyama congenital muscular dystrophy in which brain MRI findings were typical, and present this case together with a review of the literature.

The Difference of Bone Mineral Density of Lumbar Spine and Wrist in the Preterm and Full-term Infants: Using Dual Energy X-ray Absorptiometry

PURPOSE: To assess the differences in bone mineral density (BMD) of lumbar spine and wrist between preterm infants of postconceptional age 40 weeks and normal full-term infants. MATERIALS AND METHODS: Sixty-eight preterm infants born at conceptional age 26 -36 weeks and 31 normal full-term infants born at 38 -42 weeks were investigated. Bone mineral densities of the lumbar spine (from the second to the fourth segment) and wrist were measured by dual energy X-ray absorptiometry. In preterm infants, the corrected age of 0 month was defined as postconceptional 40 weeks. Full-term infants were evaluated within three days of birth, and the average bone mineral densities of preterm and full-term infants were compared. In the preterm group, birth weight and conceptional age were correlated with lumbar spinal and wrist bone mineral densities. Data were analyzed by student's t-test and Pearson's correlation coefficient, and a pvalue of less than 0.05 was considered significant. RESULTS: In preterm in fants, the values of bone mineral densities of the lumbar spine and wrist were 0.137 +/- 0.018 g/cm2(0.061 -0.202 g/cm2) and 0.089 +/-0.013 g/cm2 (0.065 -0.123 g/cm2), respectively, while the respective values for full-term infants were 0.214 +/-0.030 g/cm2 (0.160 -0.296 g/cm2) and 0.118 +/-0.014 g/cm2(0.096 -0.162 g/cm 2). In the preterm group, lumbar spinal BMD correlated significantly with conceptional age(r=0.384, p0.05). CONCLUSION: The lumbar spinal and wrist BMDs of preterm infants at corrected age 0 were lower than those of normal full-term infants. In the preterm group, BMD values for the lumbar spine were lower in infants of lower conceptional age and birth weight.

Disseminated BCG Infection in a patient with Severe Combined Immunodeficiency

Disseminated mycobacterial infection after bacillus Calmette-Guerin (BCG)vaccination is a very rare disorder, occurring mostly in patients with immunologic deficiency. We report a case of disseminated BCG infection in a 16-month-old girl with severe combined immunodeficiency. Plain radiographs showed multiple osteolytic lesions in the femora, tibiae, humerus, and phalanges. Abdominal sonography and CT scanning revealed multiple nodules in the spleen, and porto-caval lymphadenopathy.

Disseminated BCG Infection in a patient with Severe Combined Immunodeficiency

Disseminated mycobacterial infection after bacillus Calmette-Guerin (BCG)vaccination is a very rare disorder, occurring mostly in patients with immunologic deficiency. We report a case of disseminated BCG infection in a 16-month-old girl with severe combined immunodeficiency. Plain radiographs showed multiple osteolytic lesions in the femora, tibiae, humerus, and phalanges. Abdominal sonography and CT scanning revealed multiple nodules in the spleen, and porto-caval lymphadenopathy.

Sonographic Findings of Coccygeal Abscess in the Neonates

PURPOSE: The purpose of this study was to report the sonographic findings of neonatal coccygeal abscess,previously not described. MATERIALS AND METHODS: Eighteen neonates (5-18 days old) presented with swelling in thecoccygeal area and by either open drainage (n=13) or follow-up after antibiotic therapy (n=5), this was diagnosedas coccygeal abscess. We retrospectively reviewed the size, shape, location, echo pattern and marginalcharacteristics of the abscesses, as seen on sonography, as well as their intradural content and relationship withthe spine. Additional MR images (n=5) were separately reviewed. RESULTS: Mean longest diameter of the abscesseswas 1.5cm (range, 0.8-2.3); they were oval or round and located in the subcutaneous fat layer. Echogenicitycompared with surrounding fat varied: in nine patients it was isoechoic, and in nine, hypoechoic. Internalechogenicity was homogenous in 14 patients and heterogeneous in four, and in seven cases, the margin of theabscess was well demarcated. Intradural structure and bony spines were normal, and the possibility of spinaldysraphism, could thus be excluded. All cases except one were correctly diagnosed by sonography and clinicalfindings; on sonography, the echogenicity of one lesion was exactly the same as that of lipoma, and it was thusmisdiagnosed. In cases where sonography revealed an isoechoic mass, the use of MR excluded the possibility oflipoma. Three of five cases showed marginal or diffuse enhancement on contrast enhanced MR images. CONCLUSION: Coccygeal absesses were confined to the subcutaneous fat layer and were either iso- or hypoechoic compared. withsurrounding fat. In neonates, abscess formation in the coccygeal area is possible, and coccygeal abscess shouldtherefore be included in the differentiation of coccygeal masses.

The Difference in the Appearance of Proximal Humeral Epiphyseal Ossification Center on Chest Radiograph between the preterm and Full-term Infants

PURPOSE: To assess the difference in the appearance of the proximal humeral epiphyseal ossification center, as seen on chest radiograph, between preterm and full-term infants at the same corrected ages. MATERIALS AND METHODS: Forty two preterm infants born at 26-35 weeks of gestational age and 218 normal full-term infants born at 38-42 weeks were investigated. Because of various perinatal problems, the preterm infants were treated at a neonatal intensive care unit. Proximal humeral epiphyseal ossification centers were evaluated from chest radiographs, and in cases of preterm infants, the corected age of 0 month was defined as postconceptional 40 weeks. In preterm infants, the numbers of chest radiographs obtained were 42 at 0 month, 40 at 1 month, 37 at 2 months and 36 at 3 months of corrected age, while in those who were full-term, the numbers were 103 cases at 0 month, 42 at 1 month,42 at 2 months and 31 at 3 months of age. In the preterm group, alkaline phosphatase, calcium, phosphorus levels and simple wrist radiographs were checked. We then evaluated the difference of appearance of the proximal humeral epiphyseal ossification center between preterm and full-term infants at the same corrected ages, as well as the difference between causative diseases, between the normal and abnormal serologic group and between the normal and abnormal wrist group in preterm infants at the same corrected ages. Using Fisher's exact test, the data were analysed. RESULTS: The incidences of the proximal humeral epiphyseal ossification center in preterm infants were 2.4% (1/42) at 0 month, 20.0% (8/40) at 1 month, 43.2% (16/37) at 2 months and 69.4% (25/36) at 3 months; infull-term infants, the figures were 24.3% (25/103) at 0 month, 66.7% (28/42) at 1 month, 83.3% (35/42) at 2 months and 90.3% (28/31) at 3 months. At 0, 1, and 2 months, the incidences were thus seen to be lower in preterm than infull-term infants(p0.05). In preterm infants, there were no statistical differences between causative diseases, between the normal and abnormal serologic group and between the normal and abnormal wrist group(p>0.05). CONCLUSION: Up to the age of two months, the proximal humeral epiphyseal ossification center of preterm infants appears later than that of full-term infants at the same corrected age.

The Usefulness of Whole Body Bone Mineral Densitometry in the Osteopenia of Preterm Infants: Comparison with the Wrist Radiography and Biochemical Parameters

PURPOSE: To evaluate the usefulness of whole body bone mineral densitometry in the diagnosis of frequent osteopenia of preterm infants by comparison with the wrist radiographs and biochemical parameters. MATERIALS AND METHODS: From January 1995 to January 1996, we obtained whole body bone mineral density(BMD) studies using dual energy X-ray absorptiometry(DXA) and wrist radiographs of 39 preterm infants. They were divided into three groups according to birth weight, under 1500g, 1501g to 2000g and above 2000g, and four grades of skeletal change, as seen on wrist radiography, according to the scoring method of Koo et al. Groups of birth weight and grades of skeletal change were then correlated with whole body BMD and biochemical parameters. For comparison, normal data were obtained from 13 infants born at full term. Data were analyzed by one way analysis of variation(ANOVA) and correlation and regression analysis. A p-value of less than 0.05 was considered significant. RESUTLS: Whole body BMDs were significantly lower in the more premature and smaller birth weight infants(r=0.77, p=0.0000), and in the higher grade of skeletal change (r=-0.5276, p=0.0000). Aggravated skeletal changes were found in infants with lower birth weight(r=-0.3822, p=0.01). Interobserver variation in grading skeletal change was 42.9%, and intraobserver variation was 18.4%. Biochemical parameters such as serum calcium, phosphate, alkaline phosphatase, parathromone, calcitonin and 25-hydroxy-vitamine D did not vary significantly according to either birth weight or skeletal change (p>0.05). CONCLUSION: Premature osteopenia is more effectively diagnosed by measuring whole body BMD using DXA than by grading radiographical skeletal change or by biochemical parameters.

Incidence of the Appearance of the Proximal Humeral Ossification Center of the Neonates and Infants on Plain Chest Radiograph

PURPOSE: To ascertain the incidence of proximal humeral epiphyseal ossification centers, as shown on chest radiographs, in neonates and infants. MATERIALS AND METHODS: The distribution of corrected age(CA) of the infantswas from 24 weeks of gestational age to 6 months of postnatal age. They were obtained from inborn and outborn infants without developmental problems. Proximal humeral epiphyseal ossification centers were evaluated by two radiologists from a total of 440 chest radiographs. Of these, 196 were of the female chest and 244 were of themale. Corrected ages based on postnatal age are expressed as weeks before two months of age and as months after two months of age. The ossified or nonossified epiphyses of the humeral heads were plotted against corrected age. From these graphs, the percentages of ossification according to their corrected age was observed. RESULTS: 37weeks of corrected age in which 9.1%(1/11) was ossified was the earliest age of humeral epiphyseal ossification in the female. While 35 weeks of CA in which 6.3%(1/16) was ossified was the earliest age in the male. In full-term neonates(=40 weeks of CA), 20%(6/30) of epiphysis was ossified in the female and 23.3%(7/30) in the male. The female group of 43-44 weeks of corrected age showed ossification of 50% and the male group of 44-45 weeks of corrected age showed ossification of 50%. By five months of corrected age, 100% of epiphyses, both in the female and in the male, were ossified. CONCLUSION: Humeral ossification centers are seen from 35-37 weeks of correctedage. By five months of age, all humeral epiphyses are ossified.