Congenital toxoplasmosis: continued parasite proliferation in the fetal brain despite maternal immunological control in other tissues.

BACKGROUND: Congenital toxoplasmosis is a serious condition but little is known of the natural history of parasite development and associated fetal tissue destruction. METHODS: Two cases identified by ultrasound underwent induced abortion at 21 and 30 weeks' gestation. At autopsy, the placenta and fetal organs were examined by histology and immunocytochemistry employing anti-Toxoplasma stage-specific antibodies to confirm diagnosis and also provide information on the stage of parasite development. RESULTS: In both cases, maternal serology prior to termination showed both specific immunoglobulin M (IgM) and immunoglobulin G (IgG), whereas retrospective analysis of an earlier sample (12-14 weeks' gestation) showed only IgM reactivity consistent with infection occurring in the first trimester. The finding of a number of tissue cysts but few or no tachyzoites within the placenta and fetal adrenal and heart is characteristic of a chronic infection. However, in contrast, there were still areas of the fetal brain with large numbers of actively dividing, tissue-destructive tachyzoites. CONCLUSIONS: These observations show that continued parasite proliferation and tissue destruction can occur within the fetal brain even when there is a marked maternal immune response including maternal IgG. This finding strongly suggests that there may be benefits from treating cases of recently acquired congenital infection to destroy any remaining proliferating parasites located in immunologically protected sites such as the fetal brain.

Challenges in the prenatal and post-natal diagnosis of mediastinal cystic hygroma: a case report.

INTRODUCTION: Cystic hygroma is a benign congenital neoplasm that mostly presents as a soft-tissue mass in the posterior triangle of the neck. Pure mediastinal lesions are uncommon; the vast majority are asymptomatic and are an incidental finding in adulthood. The diagnosis is often made intra- or postoperatively. Prenatal identification is exceptional and post-natal diagnosis also proves challenging. CASE PRESENTATION: We report one such case that was mistaken for other entities in both the prenatal and immediate post-natal period. Initial and follow-up antenatal ultrasound scans demonstrated a multicystic lesion in the left chest, and the mother was counselled about the possibility of her baby having a congenital diaphragmatic hernia. Initial post-natal chest radiographs were reported as normal. An echocardiogram and thoracic computed tomography scan confirmed a complex multiloculated cystic mediastinal mass. The working diagnoses were of a mediastinal teratoma or congenital cystic adenomatous malformation. At operation, the lesion was compressed by the left lung and was found to be close to the left phrenic nerve, which was carefully identified and preserved. After excision, histopathological examination of the mass confirmed the diagnosis of cystic hygroma. Postoperative dyspnoea was observed secondary to paradoxical movement of the left hemidiaphragm and probable left phrenic neuropraxia. This settled conservatively with excellent recovery. CONCLUSION: Despite the fact that isolated intrathoracic cystic hygroma is a rare entity, it needs to be considered in the differential diagnosis of foetal and neonatal mediastinal masses, particularly for juxtadiaphragmatic lesions. The phrenic nerve is not identifiable on prenatal ultrasound imaging, and it is therefore understandable that a mass close to the diaphragm may be mistaken for a congenital diaphragmatic hernia because of the location, morphology and potential phrenic nerve compression. Post-natal diagnosis may also be misleading as many mediastinal cystic masses have similar appearances on imaging. Therefore, as well as cystic architecture, special consideration needs to be given to the anatomical location and effect on local structures.

Age- and gender-specific mortality rates in childhood hypertrophic cardiomyopathy.

AIMS: Hypertrophic cardiomyopathy (HCM) is the commonest inherited cause of sudden cardiac death in children; current guidelines suggest HCM screening after 12-15 years of age. The study aims to establish the age range at highest risk. METHODS AND RESULTS: Cohort study from six regional centres of paediatric cardiology, including children presenting with sudden death; n = 150 (59% = male; 39% familial HCM). Age- and gender-specific mortality was calculated, and compared with rates calculated from the Swedish National Cause of Death Registry. There were 56 deaths within the cohort, 39 were sudden arrhythmia deaths, with 31 at <19 years of age. Between 9-13.9 years of age annual sudden death mortality averages 7.2%, vs. 1.7% after 16 years of age; P = 0.025, odds ratio for proportions 3.75 [95% confidence intervals (CI) 1.18-11.91], similar in both familial and idiopathic HCM. The risk for sudden death peaks earlier in girls (10-11 years), with male preponderance after the age of 15. National cause of death statistics confirm that the mortality rate from HCM is significantly higher in the 8-16 year olds (0.112 per 100,000 age-specific population) than in the 17-30 year olds (0.055 per 100,000; 95% CI 0.011-0.099). CONCLUSION: In families with HCM, children should be screened at an early age.

Superior mediastinal teratoma containing well-differentiated bowel.

A previously fit and well 14-month-old-girl presented with a 2-month history of worsening cough and wheeze. Chest radiograph revealed a widened mediastinum and thoracic CT showed a large mixed density mass in the superior mediastinum, consistent with a mediastinal teratoma. Her tumor markers were within the normal range. The mass was resected and found to be a mature cystic teratoma. Surprisingly, well-formed bowel-like structures were present, containing all bowel wall layers and having a ganglionated myenteric plexus. The identification of complete sections of bowel in this context is a rare finding and to the best of our knowledge has not been published previously for the mediastinal teratoma. The possibility of secondary neoplasia developing in these areas is a complicating factor.

Alveolar capillary dysplasia presenting as pneumothorax: a case report and review of literature.

Alveolar capillary dysplasia, although rare, is a universally fatal form of persistent pulmonary hypertension of the newborn. We report a case of a newborn male baby who developed respiratory distress and pneumothorax 11 h after an uncomplicated delivery. He deteriorated despite full ventilatory support and extracorporeal membrane oxygenation (ECMO). Open lung biopsy provided a diagnosis of alveolar capillary dysplasia and decision was made to withdraw treatment.