Perinatal renal venous thrombosis: presenting renal length predicts outcome.

BACKGROUND: Renal venous thrombosis (RVT) is the most common form of venous thrombosis in neonates, causing both acute and long term kidney dysfunction. Historical predisposing factors include dehydration, maternal diabetes, and umbilical catheters, but recent reports highlight associations with prothrombotic abnormalities. STUDY: Twenty three patients with neonatal RVT were analysed over 15 years. Predisposing factors, presentation, and procoagulant status were compared with renal outcome using multilevel modelling. RESULTS: Median presentation was on day 1: 19/23 (83%) had pre/perinatal problems, including fetal distress (14), intrauterine growth retardation (five), and pre-identified renal abnormalities (two); 8/18 (44%) had procoagulant abnormalities, particularly factor V Leiden mutations (4/18). Long term abnormalities were detected in 28/34 (82%) affected kidneys; mean glomerular filtration rate was 93.6 versus 70.2 ml/min/1.73 m2 in unilateral versus bilateral cases (difference 23.4; 95% confidence interval 6.4 to 40.4; p = 0.01). No correlation was observed between procoagulant tendencies and outcome, but presenting renal length had a significant negative correlation: mean fall in estimated single kidney glomerular filtration rate was 3 ml/min/1.73 m2 (95% confidence interval 3.7 to -2.2; p = 0.001) per 1 mm increase, and kidneys larger than 6 cm at presentation never had a normal outcome. CONCLUSIONS: This subgroup of neonatal RVT would be better termed perinatal RVT to reflect antenatal and birth related antecedents. Prothrombotic defects should be considered in all patients with perinatal RVT. Kidney length at presentation correlated negatively with renal outcome. The latter, novel observation raises the question of whether larger organs should be treated more aggressively in future.

Pseudotumoral cystitis in children: a review of the ultrasound features in four cases.

Pseudotumoral cystitis is an uncommon inflammatory condition which may masquerade as a bladder tumour in children. There are a variety of clinical presentations such as haematuria, dysuria, infection and obstruction. Reported causative factors include infection (bacterial, fungal and parasitic) and allergy. Ultrasound is an excellent imaging modality for demonstrating this intravesical lesion although the spectrum of features is poorly described in the literature. We report our recent experience of four patients with pseudotumoral cystitis and describe the clinical features and ultrasound appearance of this condition in children.

The natural history of the multicystic dysplastic kidney in children.

The objective of this study was to examine the natural history of the multicystic dysplastic kidney and the use of sonography for follow-up studies. A retrospective study was performed on 66 children with a radiological diagnosis of multicystic kidney. The change in size demonstrated on sonograms was examined. Adequate follow-up was available on 55 children over a period of 32 months (range 2-69 months). 40/55 of the kidneys underwent a reduction in size, including 22 which were no longer detectable by ultrasound. 10/55 kidneys showed an increase in size and 5/55 showed no change. Reduction in size occurred at a mean age of 84 weeks (range 20-120 weeks). In conclusion, most multicystic kidneys undergo partial or complete involution over the first 2 years of life. The mean size of the multicystic kidney at diagnosis is a poor predictor of eventual outcome.

Spinal ultrasound in infants.

This paper discusses the indications for spinal ultrasound, including its advantages and disadvantages compared with spinal MRI. The features and ultrasound findings both in normal infants and in those with spinal dysraphism are reviewed.

Comparison of aortography, renal vein renin sampling, radionuclide scans, ultrasound and the IVU in the investigation of childhood renovascular hypertension.

The results of the investigations of all patients who underwent renal arteriography for hypertension due to renovascular disease over a three and a quarter year period prior to January 1st 1981 are reviewed and discussed. The experience gained has helped demonstrate the usefulness of DMSA scans, segmental renal vein renin estimations, and AP and oblique selective renal arteriograms with macroradiography.

Duplex Doppler ultrasound in the investigation of occult nephropathy following haemolytic uraemic syndrome.

Duplex doppler ultrasound has been reported to be of value in the detection of raised vascular resistance, particularly in the renal tract. A prospective single blind study investigating the use of duplex Doppler ultrasound to measure resistive index (RI) in patients with impaired renal function and a history of diarrhoea-associated haemolytic uraemic syndrome (D+ HUS) was performed. There was considerable overlap in the range of RIs, with RIs greater than 70% in children with normal renal function and in those with renal impairment following D+ HUS. There was no significant difference in the mean RI between the groups studied. We feel that the RI is not of value in predicting the presence of occult nephropathy following haemolytic uraemic syndrome.

The investigation of renovascular hypertension in children: the accuracy of radio-isotopes in detecting renovascular disease.

Renovascular disease is an important cause of hypertension in children because it is potentially treatable by surgical or angioplasty techniques. The aim of this study was to assess the accuracy of radio-isotopes (DMSA, DTPA and MAG3) combined with the angiotensin converting enzyme inhibitor, captopril, in detecting children with renovascular hypertension. We retrospectively reviewed the ultrasound and pre- and post-captopril radionuclide studies (either DMSA and/or DPTA and/or MAG3) of children with sustained hypertension investigated at our institution. Renal angiography was used as the 'reference technique'. Thirty-nine children, over a period of 10 years, were evaluated: 17 (44%) children had renovascular disease that involved the proximal three divisions of the renal arteries, some of which were amenable to treatment. The overall sensitivity, specificity, positive predictive value and negative predictive value for detecting such renovascular disease, as assessed by changes between pre- and post-captopril radio-isotope studies, were disappointing at 59%, 68%, 59% and 68%, respectively. When considering only abnormalities in post-captopril studies, these indices were 82%, 41%, 52% and 75%, respectively. Three children with potentially treatable renovascular disease were not identified on the captopril studies. We conclude that renal angiography should remain the 'reference technique' in identifying children suspected of renovascular hypertension.

The value of radiological investigations in pre-endoscopic assessment of children with stridor.

The differential diagnosis of stridor in an infant depends on a careful history and examination, followed by radiological and endoscopic investigations. Currently a chest, lateral neck and antero-posterior, high kilovolt (Cincinnatti) view radiographs in association with a diagnostic barium swallow are performed prior to the definitive diagnostic procedure of microlaryngobronchoscopy. Our impression was that some of the routinely ordered radiological investigations were of limited value in the differential diagnosis. We undertook a retrospective audit study to determine the value of radiological investigations in the pre-endoscopic assessment of infants with stridor. The radiological and endoscopic information of 100 infants presenting over the three-year period 1991-1993 at Great Ormond Street Hospital, London (a tertiary referral centre) was collected. It was found that only five out of 65 barium swallow investigations performed had consistent positive findings at diagnostic microlaryngobronchoscopy. The lateral neck and Cincinnatti views identified many of the more gross pathologies of the larynx and trachea e.g. the space occupying lesions, which occur infrequently. The more common diseases e.g. laryngomalacia or subglottic stenosis are rarely identified radiologically. Our results confirmed that radiology had a limited screening role and that in a child presenting with stridor the initial radiological assessment should be a chest radiograph with further imaging and a barium swallow only if an abnormality is found at microlaryngobronchoscopy.

Laryngeal ultrasound to assess vocal fold paralysis in children.

The purpose of this study was to assess the practicality and validity of laryngeal ultrasound to establish vocal fold movement in children with suspected vocal fold palsy. Fifty-five consecutive patients (age range three days to 12 years) with suspected vocal fold palsy underwent both laryngoscopy and laryngeal ultrasound. Ultrasonographic findings correlated with endoscopic findings in 81.2 per cent of cases. This, however, rose to a concordance rate of 89.5 per cent in patients aged over 12 months. Laryngeal ultrasound is well-tolerated, safe and non-invasive and the authors feel that it is a useful adjunct to endoscopy in the diagnosis of vocal fold palsy.

Oral fluid for the serological and molecular diagnosis of measles.

OBJECTIVES: Since measles presents mostly in children, a non-invasive sample collection technique such as oral fluid sampling would be very useful in the early detection of measles RNA and antibodies. The aim of this study was to validate the detection of anti-measles IgM and measles virus RNA in oral fluid and to make a comparison with the gold standard methods of ELISA using serum (Enzygnost(®) anti-Measles IgM) and in-house nested reverse transcriptase polymerase chain reaction (RT-PCR) using nasopharyngeal secretions. METHODS: Three samples each from 73 measles-positive and 44 measles-negative subjects (serum, oral fluid, and nasopharyngeal secretions) were analyzed. RESULTS: The anti-measles IgM ELISA (MicroImmune) on oral fluid was validated against the IgM ELISA (Siemens) for serum and this resulted in a sensitivity of 92% and specificity of 100%. A molecular nested RT-PCR using oral fluid was validated against the standard assay on nasopharyngeal secretions and gave a sensitivity of 100% and specificity of 100%. CONCLUSIONS: The results confirm that both serological and molecular oral fluid assays are suitable for routine use. The use of oral fluid samples for the detection of measles virus may encourage patients, general practitioners, and pediatricians to participate in the Belgian measles surveillance system and other epidemiological studies in the framework of the World Health Organization elimination program.

Postnatal investigation of fetal renal disease.

The antenatal ultrasound diagnosis of renal tract abnormalities is now firmly established. Postnatal imaging protocols are constantly evolving and still many questions remain unanswered. Most infants are asymptomatic at birth and aggressive imaging is unwarranted both for the infant and overburdened Radiology departments. The urgency with which to undertake imaging relates to the suspected antenatal diagnosis and clinical scenario, with bilateral hydronephrosis, posterior urethral valves and complicated duplex systems taking a high priority. The main imaging modality postnatally remains ultrasound, and together with nuclear medicine gives a powerful combination of both anatomy and function. Intravenous urography is never indicated in the neonate.

Ultrasound of the spinal cord in children: its role.

This article covers the indications for spinal ultrasound including its advantages and disadvantages in comparison with spinal MR. We describe the features of a normal spinal ultrasound and those features which may be found in infants with spinal dysraphism.

Primary vesicoureteric reflux--how useful is postnatal ultrasound?

The presence or absence of pelvicalyceal dilatation on postnatal ultrasound continues to appear within diagnostic algorithms to select patients for micturating cystourethrography (MCU) in the investigation of antenatally diagnosed hydronephrosis. Postnatal ultrasound findings were assessed in a population diagnosed as having antenatal hydronephrosis due solely to primary vesicoureteric reflux (VUR) to see whether this is justified. The postnatal ultrasound and MCU findings in 177 patients with primary VUR detected as antenatal hydronephrosis were reviewed retrospectively. A total of 132 (75%) were boys. Reflux was unilateral in 103 cases and bilateral in 74 (42%). Altogether 37% of boys and 33% of girls with a renal pelvic diameter of < or = 10 mm had grade III-V VUR. Calyceal and/or ureteric dilatation had specificities of 87-96% for grade III-V VUR, but sensitivities of only 37-54%. Fifty eight per cent of male and 75% of female renal units with grade III VUR and 17% of male units with grade IV-V VUR were normal on ultrasound. Approximately 25% of ultrasonically normal renal units had grade III-V VUR on MCU. Postnatal ultrasound criteria correlate poorly with the presence and degree of VUR in children with antenatally diagnosed hydronephrosis and should not be used to direct the use of cystography.

Transient sexual precocity and ovarian cysts.

Nine girls presenting under the age of 7 years with unsustained sexual precocity are described. Large ovarian cysts were detected by ultrasound in three and laparotomy in one. In two girls the symptoms resolved after surgical removal of the cyst; the other seven had spontaneous remission of symptoms, but in two of these transient breast development and bleeding recurred: further ovarian cyst formation was found in one of these patients. Endocrine studies performed before resolution of the cysts showed raised plasma oestradiol concentrations (64 to 440 pmol/l) in three girls and no appreciable rise in plasma luteinising hormone after gonadotrophin releasing hormone stimulation in two. We conclude that ovarian cyst formation with spontaneous resolution may cause transient sexual precocity in girls, and that ultrasound examination is an effective means of diagnosing and following these patients.

Colloid cyst in ectopic thyroid gland.

A five year old girl presented with a mid-line neck swelling. At operation, a multiloculated cyst was excised with a portion of hyoid bone and a suprahyoid gelatinous tract extending into the base of the tongue. Histology revealed a benign colloid cyst with associated thyroid tissue. Post-operative investigations indicated severe hypothyroidism. The cystic nature of the lesion was misleading at operation and pre-operative thyroid ultrasonography (US) is recommended for all patients with suspected thyroglossal tract cysts (TGC).