Novel Point Mutations in the NKX2.5 Gene in Pediatric Patients with Non-Familial Congenital Heart Disease

Background and objective: Congenital heart disease (CHD) is the most common birth abnormality in the structure or function of the heart that affects approximately 1% of all newborns. Despite its prevalence and clinical importance, the etiology of CHD remains mainly unknown. Somatic and germline mutations in cardiac specific transcription factor genes have been identified as the factors responsible for various forms of CHD, particularly ventricular septal defects (VSDs), tetralogy of Fallot (TOF), and atrial septal defects (ASDs). p. NKX2.5 is a homeodomain protein that controls many of the physiological processes in cardiac development including specification and proliferation of cardiac precursors. The aim of our study was to evaluate the NKX2.5 gene mutations in sporadic pediatric patients with clinical diagnosis of congenital heart malformations. Materials and methods: In this study, we investigated mutations of the NKX2.5 gene’s coding region in 105 Iranian pediatric patients with non-familial CHD by polymerase chain reaction-single stranded conformation polymorphism (PCR-SSCP) and direct sequencing. Results: We observed a total of four mutations, of which, two were novel DNA sequence variants in the coding region of exon 1 (c. 95 A > T and c. 93 A > T) and two others were previously reported as single-nucleotide polymorphisms (SNPs), namely rs72554028 (c. 2357 G > A) and rs3729753 (c. 606 G > C) in exon 2. Further, observed mutations are completely absent in normal healthy individuals (n = 92). Conclusion: These results suggest that NKX2.5 mutations are highly rare in CHD patients. However, in silico analysis proves that c.95 A > T missense mutation in NKX2.5 gene is probably pathogenic and may be contributing to the risk of sporadic CHD in the Iranian population.

Learning from defects using a comprehensive management system for incident reports in critical care

Incident reporting systems are often used without a structured review process, limiting their utility to learn from defects and compromising their impact on improving the healthcare system. The objective of this study is to describe the experience of implementing a Comprehensive Management System (CMS) for incident reports in the ICU. A physician-led multidisciplinary Incident Report Committee was created to review, analyse and manage the department incident reports. New protocols, policies and procedures, and other patient safety interventions were developed as a result. Information was disseminated to staff through multiple avenues. We compared the pre- and post-intervention periods for the impact on the number of incident reports, level of harm, time needed to close reports and reporting individuals. A total of 1719 incidents were studied. ICU-related incident reports increased from 20 to 36 incidents per 1000 patient days (P=0.01). After implementing the CMS, there was an increase in reporting 'no harm' from 14.2 to 28.1 incidents per 1000 patient days (P<0.001). There was a significant decrease in the time needed to close incident report after implementing the CMS (median of 70 days [Q1-Q3: 26-212] versus 13 days [Q1-Q3: 6-25, P<0.001]). A physician-led multidisciplinary CMS resulted in significant improvement in the output of the incident reporting system. This may be important to enhance the effectiveness of incident reporting systems in highlighting system defects, increasing learning opportunities and improving patient safety.

Can renal scan findings predict biopsy-proven allograft rejection?

OBJECTIVES

To assess the usefulness of isotopic renogram in diagnosing acute renal graft rejection.

MATERIALS AND METHODS

Degree of perfusion and allograft uptake of tracer were correlated with the clinical and biopsy diagnoses in 15 postrenal transplant patients with varying degrees of renal impairment. Renographic findings and perfusion calculations were done by a blinded observer.

RESULTS

A strong correlation was found between renal histology and renal scan findings in 13 of 15 patients. Sensitivity and specificity of renal scanning in diagnosing acute rejection were 85% and 50% respectively (using renal biopsy findings as the gold standard).

CONCLUSION

Our results demonstrate a strong correlation between blinded perfusion assessment and biopsy-proven acute rejection. We conclude, therefore, that single renal flow scan with DTPA (noninvasive/nonnephrotoxic) allows a physician to tailor therapy for acute renal graft dysfunction. We suggest that in cases with a renographic diagnosis of AR, the patient should receive standard antirejection therapy. Renal biopsy should be reserved for those instances when the renographic findings are not definitive and those when the patient fails to respond to a standard methylprednisolone therapy.

Changing trends in the obstetric indications for cervical cerclage

Cervical incompetence causes repeated mid-trimester miscarriage and preterm delivery with high fetal wastage. Since the introduction of cervical cerclage in 1951, it has undergone many changes with regard to the techniques, indications and postoperative care. The objective of this study is to review the changing trends in the current indications of cervical cerclage and subsequent perinatal outcome at the maternity hospital from January 1992 to December 1999. All the files of women who had had cervical cerclage were evaluated in terms of characteristics of the women, indications and obstetric outcome after cervical cerclage. Of 65539 who delivered in the hospital, 1021 women had had cervical cerclage, giving an incidence of 1.21%. There was a significant increase in the incidence of cervical cerclage, from 1.13% in 1992 to 1.40% in 1999 (P < 0.01). More women with multiple pregnancy in 1996 - 99 had cerclage than in 1992 - 94 period [22.7 vs. 8.5% (P < 0.01)]. It is clear that more cervical sutures are being performed in multiple pregnancies arising from assisted reproductive technology as well as after ultrasonographic evidence of cervical dilatation. A multicentre randomised clinical trial is therefore advocated to evaluate its effectiveness in these cases.

Nitric oxide production is not altered in preeclampsia

BACKGROUND

Preeclampsia remains a disease of theories as the real aetiology has remained elusive. Altered nitric oxide production has been associated with preeclampsia although conflicting results showing elevation, decrease or no change in nitric oxide levels have emerged from previous studies.

OBJECTIVE

The aim of the study was to measure the serum levels of nitrate and nitrite in normal pregnancies and pregnancies complicated by pre-eclampsia.

MATERIALS AND METHODS

Venous blood was extracted from 39 normal pregnant women (control) and 34 women with preeclampsia (study group). Serum concentrations of nitrate and nitrite were determined using the HPLC method. Other special investigations including renal function tests were performed. The patients were managed according to protocol and the outcome of the pregnancies evaluated.

RESULTS

There was no significant difference in the mean maternal age and gestational age at delivery between the groups. However the mean systolic and diastolic blood pressure of the study group (150.5 mmHg and 98.8 mmHg) were significantly higher than the levels in the control group, (110.86 and 85.5), p<0.0001. There was no significant difference in the mean serum nitrate levels (19.157+/-13.407 vs. 19.189+/-16.805) p=0.993. The fetal and maternal outcomes were comparable.

CONCLUSION

Our study has demonstrated that there was no alteration in nitric oxide production in preeclampsia, thus contributing to the existing unresolved role of nitric oxide in the pathogenesis of preeclampsia. Further research is called for.

Impact of hepatitis C virus infection on kidney transplant outcome

One hundred and forty kidney transplant recipients were evaluated to study the impact of hepatitis C virus (HCV) infection on patient and graft outcome. There .were 98 males arid 42 females with a mean age of 32.1 +/- 13 years. The duration of follow-up ranged from 6-60 months with a mean period of 27.8 +/- 18.2 months. Seventy-four (53%) patients had received cadaveric kidneys while 66 (47%) received living donor grafts. Anti-HCV reactivity was tested using second generation enzyme-linked immunosorbent assay and positivity was confirmed by recombinant immunoblot assay. HCV infection was diagnosed in 29 cases (20.7%) while HBsAg was found in nine (6.4%) and concomitant anti-HCV and HBsAg positivity was observed in two patients (1.4%). Seventeen of 29 (58.6%) patients with anti-HCV reactivity showed elevated ALT levels as against 17 of 111 (17.3%) anti-HCV non-reactive patients (P< 0.001). There was no association between the sex of the patient, source of the graft, and anti-HCV reactivity. Serum creatinine values were higher in the anti-HCV positive group, but this did not rank to statistical significance. We observed a significantly higher graft loss among the anti-HCV reactive group (27.6% versus 1.8%, P< 0.003). Thirteen anti-HCV reactive patients were subjected to 18 liver biopsies; the commonest lesion observed was chronic active hepatitis, which was progressive in two patients subjected to re-biopsy. We conclude that HCV infection is a serious health problem among kidney transplant recipients and it significantly affects the graft outcome.

Kidney transplantations at King Faisal Specialist Hospital and Research Centre

During the five year period from 1987G to 1991G, 161 kidney transplantations were performed at King Faisal Specialist Hospital and Research Centre (KFSH&RC); 79 from cadaveric donors (CD) and 82 from living related donors (LRD). All cadaveric kidneys except one were harvested within Saudi Arabia and 67% were from Saudi nationals. The immunosuppresive protocol was a triple drug regimen comprising cyclosporin-A (CyA), azathioprine (Aza), and prednisone. The actuarial graft survival rates at one and three years were 85% and 76% for the cadaveric donor transplants and 96% and 91%, respectively for the living related donor transplants (P<0.01). The corresponding patient survival rates for cadaveric donor transplants (CDTxs) were 97% and 94% and for the living related donor transplants (LRDTxs), 99% and 97% (NS). These results compare well with the best results in the Western world. The most serious surgical complications were vascular thromboses (five cases) and infections of the arterial anastomosis line with bleeding (two cases), all leading to loss of the cadaveric graft. The most common causes of death were virus infection, varicella, cytomegalovirus, and hepatitis B and C. The organ donation rate, from cadaveric donors as well as living related donors, is stil low in Saudi Arabia. Lack of organs is the main obstacle to an expansion of this promising transplantation activity. Continuous education of the multinational medical profession as well as the lay population is necessary to improve the situation.

The effect of extracorporeal high blood flow rate on left ventricular function during hemodialysis--an echocardiographic study

The effect of increased extracorporeal blood flow rate on left ventricular (LV) function has been studied during volume-controlled bicarbonate hemodialysis. Ten stable patients on chronic hemodialysis, with a mean age of 28 years (range 19-38) were studied using two-dimensional and Doppler echocardiography. The mean time on hemodialysis was 32 months (range 3-60). All patients were investigated during three dialysis sessions on the first day of the week for 3 consecutive weeks. The blood flow rate was chosen randomly as 250, 350, or 450 cc/min. Apart from the time of hemodialysis and blood flow rate, other parameters of the hemodialysis were kept stable during all three sessions. Echocardiographic studies were done before, at mid dialysis, and during the last 15 min of each dialysis session. The following parameters were evaluated: heart rate, mean blood pressure, shortening fraction, ejection fraction, cardiac output, and pre-ejection period/LV ejection time ratio. The changes of the measured cardiac parameters at the beginning, middle and end of each session were not significantly different. Furthermore, the differences in changes between the three different sessions were comparable. Our results indicate that an increase in dialysis blood flow rate up to 450 cc/min does not have an adverse effect on the left ventricle in patients on maintenance hemodialysis and with stable cardiovascular function.

Hepatitis C virus infection in chronic haemodialysis patients, a clinicopathologic study

Fifty-two patients on regular haemodialysis at our institution were evaluated for the presence of HCV infection. Evaluation included detailed history, clinical examination, and monthly screening for anti-HCV antibody, liver enzymes (ALT, AST), serum iron and ferritin. Also, three-monthly screening for other viral markers, HBV (HBsAg, HBsAb, HBcAb), CMV (IgG and IgM), EBV, and HIV. Anti-HCV antibody was found in 21 patients (40.4%). There was a significant (P less than 0.05) relationship between presence of anti-HCV antibody and proportion of patients who received blood transfusion. During a 12-month follow-up, four (11.4%) patients seroconverted to be Anti-HCV positive while one case (4.8%) seroconverted to be anti-HCV negative. The frequency of elevation of liver enzymes was significantly higher in Anti-HCV positive cases (14/18) than in negative cases (11/28, P = 0.01). Evaluation of liver biopsies of 13 patients showed chronic persistent hepatitis in six and chronic active hepatitis in seven cases. We concluded that hepatitis C is a common problem among chronic haemodialysis patients at our institution; HCV infection is documented in 70% of all clinically diagnosed NANB hepatitis. Presence of anti-HCV antibodies cannot differentiate between active and past infection and cases with early HCV infection can be missed when relying on the mere detection of anti-HCV antibodies.

Aluminium overload and response to recombinant human erythropoietin in patients under chronic haemodialysis

In this work, of 51 patients treated by rHuEpo, 25 were selected for study. The selection criteria were absence of clinically evident causes of anaemia other than end-stage renal failure, such as chronic infection, active systemic disease, bleeding sites, and vitamin B12 or iron deficiencies. Serum aluminum was assessed before dialysis and the presence of aluminium overload was confirmed by a DFO test. rHuEpo was given in a dose of 50 U/kg body-weight after each dialysis session three times weekly and the response to treatment was evaluated monthly for 8 months. Our data showed significant correlation between serum aluminum and the response to rHuEpo. The response was significantly greater in those with lower serum aluminium. We conclude that the aluminium load in chronic haemodialysis patients may have an effect on the response to rHuEpo.

Factors predictive of post-transplant erythrocytosis

Ninety-three patients with PTE (that is, hematocrit 51% or greater) were identified among 431 renal transplant recipients, an incidence of 21.6%. Thirty-eight patients underwent blood volume measurements, and 22 of these had high red cell volume and therefore were considered to have true PTE. To analyze factors predictive of erythrocytosis, a control group with normal hematocrit was randomly selected from our renal transplant population and compared with the 93 patients with PTE, and with the 22 who had true PTE. Using step-wise logistic regression analysis, we identified three variables that were consistent predictors of PTE. In order of significance, the serum creatinine value at the onset of PTE appears to most strongly predict the occurrence of PTE (P less than 0.0001). As creatinine value increases, the probability of PTE decreases. Next was immunosuppression, where double immunosuppressive therapy was associated with a greater probability of PTE than triple therapy (P less than 0.0001). The overall incidence of PTE in patients on double therapy was 34%, while that for those on triple therapy 10.4%. Last was duration of dialysis for which increasing values correspond to increasing probability of PTE (P = 0.004). Comparison of the serum erythropoietin (EPO) levels for patients and controls yielded a nonsignificant result (P = 0.2507 and P = 0.383 for all patients with PTE and true PTE, respectively), and therefore EPO levels were inappropriately elevated for the level of hematocrit in the PTE group. Only the number of rejections and duration of follow-up (r = -0.3507) were significantly correlated with EPO (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Mycobacterial infection after renal transplantation--report of 14 cases and review of the literature

During a nine-year period, 14 cases of mycobacterial infection (tuberculosis) developed in 403 renal transplant recipients at the King Faisal Specialist Hospital and Research Centre in Riyadh, Saudi Arabia, an incidence of 3.5 per cent. The annual incidence of tuberculosis was about 50 times higher than that in the general population. Infection was disseminated in nine (64.3 per cent), pulmonary in four (28.6 per cent), and genitourinary in 1 (7.1 per cent). In one patient tuberculosis was transmitted by the donor's kidney. The clinical manifestations were often ill-defined and not different from that in the normal host. Cultures from all patients grew Mycobacterium tuberculosis; concomitant infection with other organisms was present in five patients (35.7 per cent). Two of 18 patients (group 1) with positive pretransplant tuberculin skin test developed tuberculosis after transplantation (11 per cent), and neither received isoniazid prophylaxis; three of 70 patients (group 2) with negative skin tests developed tuberculosis after transplantation (4.3 per cent). The difference between the two groups was not statistically significant. Review of all published cases of mycobacterial infections in renal transplant recipients revealed 130 cases. Tuberculosis was disseminated in 38.7 per cent, pulmonary in 40.2 per cent, cutaneous in 12 per cent, and miscellaneous in 9.4 per cent. Atypical mycobacteria were responsible for 29 per cent of disseminated infections, 8 per cent of pulmonary infections and all cases of cutaneous and articular tuberculosis. Invasive procedures were needed to establish the diagnosis in 21 of 33 disseminated cases but in only three of 47 cases of pulmonary tuberculosis (p less than 0.0001). The mortality rate from disseminated disease was 37 per cent and from all other forms of tuberculosis was 11 per cent (p less than 0.005). These findings (1) confirm the higher incidence of tuberculosis in renal transplant recipients, compared to the general population; (2) suggest that pretransplant skin testing probably has little value in identifying patients at risk; (3) show that disseminated tuberculosis is common after renal transplantation and requires invasive procedures for diagnosis; (4) confirm that the donor kidney may be an important source of infection; and (5) indicate that concomitant infection with other organisms is common.

Kaposi's sarcoma: the most common tumor after renal transplantation in Saudi Arabia

Between September 1975 and November 1986, 263 renal transplant recipients at the King Faisal Specialist Hospital and Research Center were followed; 82 procedures were done by the authors using live related donors. Among the 263 patients, 14 cases of Kaposi's sarcoma were identified, an incidence of 5.3 percent compared with an incidence of 0.4 percent in renal transplant recipients from Western countries. In addition, two more patients had other types of tumors. Thus, Kaposi's sarcoma represents 87.5 percent of tumors in the King Faisal Hospital renal transplant population, in contrast to 3.7 percent in the Cincinnati Transplant Tumor Registry. The mean period between transplantation and diagnosis of Kaposi's sarcoma was 12.5 months (range, one to 37 months). Eleven patients were Saudis and three were other Arab nationals. Seven of the 11 Saudi patients were from the southwestern region of the country. Cytomegalovirus titers were not elevated in six of 10 patients. Results of tests for human immunodeficiency virus were negative in seven of eight patients. HLA-A2 antigen frequency was significantly increased in the King Faisal Hospital renal transplant patients with Kaposi's sarcoma as compared with a control population (83.3 percent versus 43.6 percent, p value = 0.006 [P = 0.06 with Bonferroni adjustment]), and increased, though nonsignificantly, compared with the live related kidney transplant recipients without Kaposi's sarcoma (83.3 percent versus 49.4 percent, p value = 0.058 [P = 0.58 with Bonferroni adjustment]), suggesting a genetic predisposition to Kaposi's sarcoma in these patients.

Mechanism of effect of dibutyryl cyclic adenosine 3',5'-monophosphate on canine renal renin release

We evaluated the effect of intrarenal arterial infusion of dibutyryl cyclic AMP on renal renin release. Dibutyryl cyclic AMP (300 micrograms/kg X min) produced significant and reversible increases in renin secretion rate, renal blood flow and urinary Na+ excretion. In the non-filtering kidneys, dibutyryl cyclic AMP increased renin secretion rate and renal blood flow. In indomethacin-treated dogs, dibutyryl cyclic AMP also produced significant and reversible increases in renin secretion rate and renal blood flow but had no effect on Na+ excretion. During infusion of dibutyryl cyclic AMP, infusion of the Ca ionophore A23187 failed to inhibit renin release. These findings suggest that the effect of dibutyryl cyclic AMP on renin release is not mediated by prostaglandins or intracellular Ca and does not involve the macula densa. We conclude that dibutyryl cyclic AMP has a direct effect on the juxtaglomerular cells.

Renal oncocytoma associated with diffuse lymphoma

We report on a sixty-six-year-old man with a poorly differentiated, diffuse lymphoma in whom bilateral multiple renal masses developed six months after starting chemotherapy. Computerized tomography and selective renal arteriograms were suggestive of either recurrence of lymphoma or renal cell carcinoma. Kidney biopsy revealed renal oncocytomas, benign renal tumors. The patient was spared further courses of cytotoxic therapy.

Ethylene glycol poisoning: diagnosis based on high osmolal and anion gaps and crystalluria

We report a case of ethylene glycol poisoning in a 54-year-old man found comatose on the street. No history was available. The diagnosis was based on the findings of a high anion gap metabolic acidosis, a high osmolal gap, and the presence of oxalate and hippurate crystals in the urine. The diagnosis was confirmed later by an ethylene glycol level of 775 mg/dl. This case illustrates how these parameters can be used in the emergency department for rapid diagnosis and management.

Acute drug-associated rhabdomyolysis: an examination of its diverse renal manifestations and complications

Thirty patients with drug associated acute nontraumatic rhabdomyolysis were evaluated. Acute renal failure, oliguric (ORF) in ten and nonoliguric (NORF) in another ten patients, was observed. The remaining ten patients did not develop renal failure (NRF). To identify factors that may have contributed to this clinical diversity, these three groups were compared. Data from 51 patients reported in the literature were also included in the analysis. The patients with ORF were slightly younger than patients with NORF. They had higher incidence of muscle swelling and higher serum potassium. ORF was more severe, lasted longer, and required more dialysis than NORF. The group of patients with renal failure had higher incidence of coma and more patients with very high muscle enzyme elevation than NRF patients. Hypercalcemia, a unique complication of rhabdomyolysis, was reported in 22 patients. It was not seen in patients without renal failure. There were no differences in age, incidence of coma, muscle swelling, and muscle enzyme between those who did and those who did not develop hypercalcemia. Sixteen patients with nerve entrapment had higher incidence of coma and muscle swelling than the rest of the patients.

Effect of angiotensin II and an angiotensin II inhibitor on renin secretion in the dog

This study examined the effect of angiotensin II (AII) and (Sar-1Gly-8) AII, a competitive inhibitor of AII, on renin release in anesthetized dogs. An intravenous infusion of AII (25 ng/kg per min) raised BP 24 mmHg and lowered plasma renin activity (PRA) from 18.8 plus or minus 2.8 to 6.2 plus or minus 1. 3 ng/ml per h (P smaller than .001). When the intravenous infusion of AII inhibitor (1.0 mug/kg per min) was superimposed on the AII infusion, PRA rose from 6.5 plus or minus 22 to 12.3 plus or minus 3.6 ng/ml per h (P smaller than .02). Renal hemodynamics, BP, and urinary sodium excretion (UNaV) reverted toward pre-AII control values. A small dose of AII inhibitor (0.1 mu/kg per min) was then infused into one renal artery in animals receiving the constant intravenous infusion of AII. Renin secretion rate (RSR) increased significantly, not only in the infused kidney, but also in the contralateral kidney. In the latter there were no changes in renal hemodynamics or UNaV, and RSR was unimpaired by denervation of that kidney. The results suggest that the AII inhibitor blocks both the vascular and the renin-suppressing actions of AII and that the latter effect is more susceptible to inhibition.