Seroepidemiology of hepatitis B virus infection among children in Mongolia: Results of a nationwide survey

BACKGROUND: Because Mongolia is one of the highly endemic countries for hepatitis B virus (HBV) infection in the world, hepatitis B (HB) vaccine was introduced into the National Expanded Program on Immunization in 1991. However, relatively few data are available concerning HBV infection among children born after the start of the program, so far. The aim of the present paper was to describe the seroepidemiology of HBV infection among primary school children using representative national data. METHODS: In 2004, a nationwide school-based cross-sectional serosurvey was carried out throughout Mongolia, covering both urban and rural areas. Serum samples were tested for hepatitis B surface antigen (HBsAg), antibody to hepatitis B core antigen (anti-HBc) and hepatitis B e antigen (HBeAg) as well as for liver enzymes. RESULTS: A total of 1145 children aged 7-12 years were studied, which represents nearly 2% of the second grade population of elementary schools in Mongolia. The overall prevalence of HBsAg and anti-HBc was 5.2% (95% confidence interval [CI]: 3.9-6.5%) and 15.6% (95%CI: 13.5-17.7%), respectively. Among HBsAg-positive children 67.8% (95%CI: 55.9-79.7%) were also positive for HBeAg. The prevalence of chronic HBV infection increased by age and was significantly higher among children from rural areas compared to those from urban areas (7.7% vs 3.0%; P < 0.001). In the multivariate logistic regression analysis, rural residence (odds ratio [OR]: 2.57; 95%CI: 1.45-4.58), male sex (OR: 1.9; 95%CI: 1.08-3.26) and age (OR: 1.5; 95%CI: 1.10-2.05) were independent demographic predictors for chronic HBV infection. CONCLUSIONS: The prevalence of chronic HBV infection has been decreasing in the Mongolian young generation, most likely due to infant HB vaccination. However, significant rural-urban differences in the prevalence of HBV infection were found that demand further investigation to estimate the potential causes.     

Early detection of prune belly syndrome in utero by ultrasonography

A report is presented of a male infant with prune belly syndrome (PBS) in whom bladder enlargement was detected by ultrasound (US) as early as 13 weeks of gestation. Subsequent fetal US identified progressive urinary tract dilatation, ascites and oligohydramnios. At 22 weeks, the fetal bladder was drained under US guidance. A gradual resolution of oligohydramnios was detected on US performed after 26 weeks of gestation. Delivery by cesarean section was performed at 34 weeks of gestation. The newborn had typical features of PBS with a vesico-cutaneous fistula but did not show respiratory distress. Imaging studies showed hypoplastic left kidney, slightly dysplastic but functioning right kidney, megaureter, megacystis, vesicoureteral reflux and dilated prostatic urethra. The early detection of genitourinary system abnormalities and serial US suggest that a distal urethral obstruction may be the underlying mechanism of PBS. Spontaneous (or therapeutic) intra-uterine decompression of the bladder might ameliorate obstructive nephropathy and oligohydramnios, allowing adequate lung development.     

Two cases of insulin-dependent diabetes mellitus under insulin treatment with slow height velocity: Relationship of growth hormone-binding protein,metabolic control and growth

Inadequate blood sugar control in children with insulin-dependent diabetes mellitus (IDDM) sometimes results in low insulin-like growth factor-I (IGF-I) and sluggish height growth. High affinity growth hormone-binding protein (GHBP), which is identical to the extracellular domain of growth hormone (GH) receptor, is present in the human sera. We have determined GHBP activity in two cases of poorly controlled IDDM with low height velocity in relation to metabolic control in order to determine the mechanism of resistance to GH in this condition, as indicated by low levels of GH-dependent growth factor IGF-I in the face of high serum GH levels. GHBP activity was within the normal range in two cases of IDDM with slow height velocity, low IGF-I and high hemoglobin-A₁. In both cases, improved blood sugar control normalized IGF-I to result in accelerated height velocity without a major change in GHBP levels. These results may indicate either normal peripheral GH receptor or normal free portion of serum GH, and may suggest that the major defect in slow growth in poorly controlled diabetes is due to the post GH receptor.     

EXPRESSION OF PARATHYROID HORMONE (PTH)-RELATED PEPTIDE (PTHrP) AND PTH/PTHrP RECEPTOR IN GIANT CELL TUMOUR OF TENDON SHEATH

The giant cell tumour of tendon sheath (GCTTS) is mainly composed of mononucleated stromal cells (SC) and multinucleated giant cells (GC), so-called osteoclast-like GC. It is thought that GC are derived from SC, but their precise relationship is not fully understood. Parathyroid hormone (PTH)-related peptide (PTHrP) is now considered to be a cytokine for cell differentiation, which may stimulate osteoclast-like cell formation in haematopoietic cells. Five cases of GCTTS were evaluated immunohistochemically, using a variety of antibodies against PTHrP, PTH/PTHrP receptor, KP-1 as a histiocytic phenotypic antigen, fibronectin as a fibroblastic phenotypic antigen, and proliferating cell nuclear antigen (PCNA). In situ hybridization and immunohistochemistry revealed that in all cases both SC and GC expressed PTHrP. PTH/PTHrP receptor was observed only in histiocytic SC and GC, but not in fibroblastic SC. Almost all GC showed histiocytic features. PCNA immunoreactivity was detected only in the nuclei of SC, and not in GC. Moreover, SC with PTH/PTHrP receptor immunoreactivity were negative for PCNA. These results suggest that GC are derived from histiocytic SC expressing PTH/PTHrP receptor and losing proliferative activity in the process of transition from mononuclear to multinucleated. PTHrP produced by SC and GC may be involved in the formation of osteoclast-like cells in GCTTS by acting in an autocrine/paracrine fashion.     

Relationship Between Diastolic Mitral Regurgitation and PQ Intervals or Cardiac Function in Patients Implanted with DDD Pacemakers

Diastolic mitral regurgitation (MR) is known to be induced by prolonging atrioventricular (AV) delay in patients implanted with a DDD pacemaker. We studied the relationship between diastolic MR and PQ intervals on cardiac function in 50 patients (71.3 ± 11.3 years old: mean ± SD), who had been implanted with DDD pacemakers. In 19 patients, prior to pacemaker implantation, pulmonary capillary wedge pressure (PCWP) was measured using a Swan-Ganz catheter during AV sequential pacing with an AV delay of 0.165 seconds. Transmitrai blood flow was measured with pulsed Doppler echocardiography, while prolonging AV delay stepwise by 0.025 seconds from 0.065 seconds for about 5 minutes each. In nine patients, AV delay could not be prolonged enough due to occurrence of intrinsic AV conduction. In the other 41 patients, diastolic MR was induced by prolonging AV delay. The critical PQ intervals that induced diastolic MR ranged from 0.14 to 0.26 (0.23 ± 0.03) seconds. Four of five patients whose critical PQ intervals were 0.20 seconds or shorter had heart failure, while 36 patients whose critical PQ intervals were >0.20 seconds were free from signs and symptoms of heart failure. Their PCWPs were 2–27 (7.5 ± 5.1) mmHg. There was a significant negative correlation between the critical PQ intervals for the appearance of diastolic MR and PCWP during AV sequential pacing, which was performed prior to pacemaker implantation (r = -0.85, P < 0.001). It is suggested that the appearance of diastolic MR is determined mainly by PQ intervals and cardiac function. Measurement of the critical PQ intervals that induce diastolic MR may be useful in assessing cardiac function in patients implanted with DDD pacemakers.     

Nestin is a novel marker for renal tubulointerstitial injury in immunoglobulin A nephropathy

Aim: Nestin, an intermediate filament originally identified as a marker of neural progenitor cells, is transiently expressed in endothelial cells and tubuloepithelial cells during kidney development. However, in adult kidneys, podocytes are the only cells that express nestin. In this study, we examined tubulointerstitial nestin expression in human glomerulonephritis. Methods: Renal biopsy specimens obtained from 41 adult patients with immunoglobulin (Ig)A nephropathy were studied. Nestin expression was determined by immunohistochemical staining and estimated by digital image analysis. To identify the phenotype of nestin‐positive cells, a double immunofluorescent study was performed for nestin and CD34 (a marker for endothelial cells) or α‐smooth muscle actin (α‐SMA, a marker for myofibroblasts). Results: In normal kidney, nestin expression was restricted to the podocytes and was not detected in tubular cells and tubulointerstitial cells. In contrast, increased nestin expression was observed at tubulointerstitial areas of IgA nephropathy. The degree of tubulointerstitial nestin expression was positively correlated with tubulointerstitial fibrosis (r = 0.546, P < 0.001). The double immunofluorescent study showed that most nestin‐positive cells in the interstitium were co‐stained with CD34 or α‐SMA, suggesting that peritubular endothelial cells and tubulointerstitial myofibroblasts express nestin during the progression of tubulointerstitial injury. In addition, strong nestin expression was associated with deterioration of renal function. Conclusion: Nestin expression is associated with tubulointerstitial injury and predicts renal prognosis in IgA nephropathy. Nestin could be a new marker for peritubular endothelial cell injury and tubulointerstitial fibrosis.     

Paroxysmal Atrial Fibrillation Maintained by Nonpulmonary Vein Sources Can Be Predicted by Dominant Frequency Analysis of Atriopulmonary Electrograms

Introduction: Increasing evidence suggests that high-frequency excitation in the pulmonary vein (PV) plays a dominant role in the maintenance of paroxysmal atrial fibrillation (AF). However, in a certain population of patients, AF remains inducible after PV isolation (PVI). We sought to clarify whether dominant frequency (DF) analysis of atriopulmonary electrograms can predict paroxysmal AF maintained by non-PV sources.
Methods and Results: Sixty-one patients with paroxysmal AF (aged 59 ± 12 years) were studied. Before PVI, bipolar electrograms during AF were recorded simultaneously from three PV ostia, the coronary sinus (CS), and the septum and free wall of the right atrium (RA). DF was obtained by fast Fourier transform (FFT) analysis. AF was rendered noninducible after PVI in 39 of the 61 patients (noninducible group), but was still inducible in the remaining 22 (inducible group). Among the six recording sites, the highest DF was documented in the PV in all of the patients in the noninducible group; the maximum DF among the three PVs (PV-DF_max) was higher than that among the CS and two RA sites (atrial DF_max; 7.2 ± 1.0 Hz vs 5.8 ± 0.7 Hz, P < 0.0001). In contrast, the highest DF was documented in the CS or RA in 45.5% of the patients in the inducible group; PV-DF_max was comparable with atrial DF_max (6.6 ± 0.8 Hz vs 6.6 ± 0.6 Hz). AF inducibility after PVI was predicted by a PV-to-atrial DF_max gradient of <0.5 Hz, with a sensitivity of 90.9% and a specificity of 89.7%.
Conclusion: Paroxysmal AF maintained by non-PV sources can be predicted by the PV-to-atrial DF gradient.     

Retroperitoneoscopic ureterocutaneostomy for obstructive uropathy with advanced bladder cancer: A case report

A 71-year-old man who had previously undergone left nephroureterectomy for renal pelvic tumor developed advanced bladder cancer with obstructive uropathy. He complained of severe macroscopic hematuria, dysuria and presented with postrenal failure. To rescue the renal function and improve ease the patient's symptoms, retroperitoneoscopic ureterocutaneostomy was performed. The operation time was 90 min and blood loss was kept to a minimum. He was able to walk and eat on the first postoperative day, and he left the hospital on postoperative day 21 with satisfactory renal function. Retroperitoneoscopic ureterocutaneostomy is simple, less invasive and a reproducible procedure for poor prognostic advanced cancer patients with obstructive uropathy.