Oxidative stress and asymmetric dimethylarginine is independently associated with carotid intima media thickness in peritoneal dialysis patients

BACKGROUND

Oxidative stress (OS) and asymmetric dimethylarginine (ADMA) are accepted as nonclassical cardiovascular risk factors in end-stage renal disease patients. To clarify the role of these factors in the atherosclerotic process, we investigated if OS and ADMA are associated with common carotid artery intima media thickness (CIMT) in peritoneal dialysis (PD) patients.

METHODS

Thirty PD patients without known atherosclerotic disease and classical cardiovascular risk factors as well as age- and gender-matched 30 healthy individuals were included. We measured serum thiobarbituric acid-reactive substances (TBARS), malondialdehyde (MDA), advanced glycation end product (AGE), pentosidine, advanced oxidation protein products (AOPP), ADMA and CIMT in each subjects.

RESULTS

TBARS, MDA, AOPP, AGE, pentosidine and ADMA levels were significantly higher in PD patients than in controls (p < 0.001). CIMT in patients was higher than in the control group (0.83 +/- 0.09 vs. 0.77 +/- 0.06 mm; p < 0.01). CIMT was independently correlated with TBARS (beta = 0.33, p < 0.01), MDA (beta = 0.27, p < 0.01), AOPP (beta = 0.22, p < 0.02), AGE (beta = 0.45, p < 0.01), pentosidine (beta = 0.56, p < 0.01) and ADMA (beta = 0.54, p < 0.01).

CONCLUSIONS

OS markers and serum ADMA levels independently predict the CIMT level in PD patients.

Mutations of chronic granulomatous disease in Turkish families

BACKGROUND

Chronic granulomatous disease (CGD) is an inherited disorder of the innate immune system characterized by impairment of intracellular microbicidal activity of phagocytes. Mutations in one of four known NADPH-oxidase components preclude generation of superoxide and related antimicrobial oxidants, leading to the phenotype of CGD. Defects in gp91-phox, encoded by CYBB, lead to X-linked CGD and have been reported to be responsible for approximately 70% of all CGD cases. The aim of this study was to identify the CGD mutations in a group of Turkish CGD patients and to evaluate the predominance of CGD mutations as X-linked or autosomal recessive (AR) within the Turkish CGD families with known mutations.

MATERIALS AND METHODS

Two Turkish CGD families were included in the study, and mutations were identified by sequence analysis of DNA and RNA from peripheral blood in the patients. Before mutation analysis, subgroup analysis of patients was made by flow cytometry with antibodies against NADPH oxidase components and with DHR-123 oxidase activity assay. For comparison, we included previously reported results from four other Turkish CGD families.

RESULTS

Two different mutations were identified, one of them a novel mutation g.700G>T located in exon 7 of CYBB, and the other a hot-spot mutation located in exon 2 of the NCF1 gene. These mutations were detected in three patients from two Turkish families.

CONCLUSIONS

Until now, we have altogether identified mutations in six Turkish CGD families. In this limited number of families our results show AR-CGD in two-thirds of the Turkish families investigated, in contrast to previous reports in the literature. This is probably due to the high rate of consanguineous marriages in Turkey. Consanguineous parents were found in 75% of the families with AR-CGD patients, which favours homozygous deficiencies.

Assessment and comparison of endothelial function between dialysis and kidney transplant patients

Dialysis and kidney transplant patients display endothelial dysfunction. Previous studies concerning comparisons of endothelial function in dialysis and kidney transplant patients included subjects with cardiovascular risk factor(s) that alone may lead to endothelial dysfunction. In this study, we compared endothelial function between dialysis and transplant patients who did not show known cardiovascular risk factors that lead to endothelial dysfunction. We studied age- and gender-matched cohorts: 30 hemodialysis (HD), 30 peritoneal dialysis (PD), and 30 kidney transplant patients. We also included 20 age- and gender-matched healthy controls. We assessed the endothelial function of patients and controls by a noninvasive technique. Serum biochemistry profiles of patients were also similar to controls in terms of lipid profile and fasting blood glucose level. Although mean FMD% levels of HD and PD patients were similar (6.6% +/- 3.1% vs 6.8% +/- 3.0%, P > .05), the mean percent of flow-mediated endothelium-dependent dilatation (FMD%) level in transplant patients was higher than those in HD or PD patients (10.50% +/- 3.0% vs 6.6% +/- 3.1% and 6.8% +/- 3.0%, respectively; P < .01). In addition, the mean FMD% level in healthy controls was higher than those in HD, PD, and transplant patients (14.0% +/- 2.3% vs 6.6% +/- 3.1%, 6.8% +/- 3.0% and 10.50% +/- 3.0%; P < .01, respectively). In conclusion, endothelial functions in transplant patients were better than those in dialysis patients.

Skewing of X-chromosome inactivation in three generations of carriers with X-linked chronic granulomatous disease within one family

BACKGROUND

Chronic granulomatous disease (CGD) is an inherited disorder of the innate immune system characterized by impairment of intracellular microbicidal activity of phagocytes. Mutations in one of the four known NADPH-oxidase components preclude generation of superoxide and related antimicrobial oxidants, leading to the phenotype of CGD. Defects in gp91-phox, encoded by CYBB, lead to X-linked CGD, responsible for approximately 70% of all CGD cases. The aim of the study was to evaluate the hypothesis that age-related skewing of X-chromosome inactivation, as described in several CGD families, is caused by preferential survival of bone marrow clones with an inactive NADPH oxidase.

MATERIALS AND METHODS

We studied the neutrophils from three patients and four carriers in three generations of a Turkish family with X-linked CGD. Carrier detection was carried out by the dihydrorhodamine (DHR)-1,2,3 assay, which measures on a per-cell basis the NADPH oxidase-dependent oxidation of DHR by phagocytes. The X-chromosome inactivation pattern was determined with the HUMARA assay in DNA from leucocytes as well as in DNA from a buccal smear of the four carriers.

RESULTS

The three patients were identified by a negative DHR test, and the mutation in their CYBB gene was characterized by DNA sequencing. Moreover, we found an age-related degree of skewing of X-chromosome inactivation in the leucocytes of the four X-CGD carriers, both at the protein level (NADPH oxidase activity) and at the DNA level (HUMARA assay). However, similar skewing of X-chromosome inactivation was found in the buccal DNA from these women.

CONCLUSIONS

These novel findings indicate that the age-related degree of skewing was probably a chance finding, not related to preferential survival of NADPH oxidase-deficient precursor cells, because this enzyme is not expressed in (buccal) epithelial cells.

Influence of tacrolimus plus mycophenolate mofetil regimens on acute rejection rate and diabetes mellitus development in renal transplant recipients

In this study we investigated the influence of a tacrolimus (TAC) plus mycophenolate mofetil (MMF) immunosuppressive regimen on the acute rejection rate and side effect profile in renal transplant recipients. The study included 80 living-related and 40 cadaveric donor renal transplant recipients (82 men, 38 women) of mean age 35 +/- 10 years (range, 16 to 58) who were operated between August 1999 and September 2002. The mean HLA mismatches was 3 +/- 1 (range, 0 to 5). All patients received prednisolone, MMF (2 g/d for the first 14 days posttransplant and then 1 g/d) plus TAC (0.2 mg/kg/d). They were followed for the development of rejection attacks and side effects. Diabetes mellitus developed in 13 patients (9 men, 4 women; 10.8%). Initially, patients required insulin therapy but after 6 months, 5 recipients no longer needed insulin therapy and were switched to oral hypoglycermic agents and diet control. Hypertension was diagnosed in 58 patients (48.3%). Neither gender nor donor origin (P =.14; P =.79, respectively) produced a significant difference in diabetes mellitus development. Biopsy proven acute rejection episodes were observed in 16 out of 120 patients (13.3%). Six out of 120 patients lost their grafts throughout the study period including one death because of suicide, one because of cytomegalovirus disease and hemophagocytic syndrome, one due to posttransplant lymphoproliferative disease and two to a cardiac arrhythmia. Only one patient lost his graft due to acute accelerated vascular rejection. Biopsy-proven chronic rejection appeared in one patient. In conclusion, although the incidence of insulin-dependent diabetes mellitus during posttransplant 6 months, seems high it decreased to 1.6% upon reduction of the TAC dosage. TAC plus MMF immunosuppression seems effective and safe in terms of acute rejection rates and side effect profiles.

Cigarette smoking in renal transplant recipients

Cigarette smoking may adversely influence patient and graft survival. In Europe and the United States the prevalence of cigarette smoking in dialysis patients is 35% to 40% and 25%, respectively. In Turkey, the estimated prevalence of cigarette smoking rate in the normal population is 26%. This study evaluated the rate of smoking in 63 cadaveric, and 158 living-related renal transplant recipients including (150 men, and 76 women of 38 +/- 12 years; range, 8 to 70) who were operated between 1986 and 2001. Demographic data were collected with a questionnaire delivered to patients during their routine outpatient visits. During this time period, 8 patients had died, 4 from hemophagocytic syndrome, 2 from cardiovascular disease, 1 from Kaposi sarcoma and 1 from a cerebrovascular accident. Twenty-three patients have lost their grafts. While at the time of transplantation 97 (42%) were smoking cigarettes, only 29 (12%) continued smoke after transplantation. Male gender significantly correlated with cigarette smoking (P =.000). Twelve smokers were single but 85 out of 97 were married, a statistically significant difference (P =.010). In contrast there was no significant relationship between pretransplant smoking and educational status (P =.354); graft loss and smoking (P =.129); or mortality and smoking (P =.224). There was a significant relationship between pretransplant and posttransplant smoking (P =.000). There was no relationship between pre- and post-transplant smoking and development of diabetes mellitus or hypertension. Interestingly the posttransplant serum albumin level was lower among smokers than nonsmokers (4.44 +/- 0.02 g/dL vs 4.30 +/- 0.02 g/dL; P =.019). There was a close relationship between transplantation duration and smoking.

Influence of inflammation on the relation between markers of iron deficiency in renal replacement therapy

Iron deficiency is an important factor in the management of anemia in both dialysis and transplant patients. Serum ferritin and transferrin saturation (TS) may be influenced by the presence of inflammation. Recently, the soluble transferrin receptor (s-TfR) has been considered to be a marker of functional iron stores. In this study, parameters of the iron state were investigated in terms of agreement (assessed by kappa) with the diagnosis of iron deficiency and with inflammation. The study was performed in 38 hemodialysis, 31 continuous ambulatory peritoneal dialysis, and 21 anemic renal transplant patients. CRP and amyloid A protein (AAP) were studied as markers of inflammation. Iron deficiency was defined as ferritin <100 mg/L, TS <20%, or s-TfR >1.76 mg/mL. We observed that s-TfR levels were significantly related to both dialysis duration (r = 0.28 in dialysis and r = 0.60 in transplant patients, both P <.05) and PTH levels (r = 0.23 in dialysis and r = 0.55 in transplant patients, both P <.05). Among the transplant group, ferritin and TS, as well as TS and s-TfR were significantly related (r = 0.84 and r = -0.64, respectively), but not s-TfR and ferritin. Among the dialysis group, ferritin and TS, and also TS and s-TfR, were significantly related (r = 0.35 and r = -0.30, respectively), whereas s-TfR and ferritin were not. In the transplant group, the kappa value for agreement between ferritin and TS in the diagnosis of iron deficiency was 0.76 (P =.006), and 0.33 (P =.04), respectively. Among patients with CRP levels <0.3 mg/L or AAP levels <6.4 mg/L, the relation between parameters of iron state was more robust. The kappa value for agreement between ferritin and s-TfR was 0.49 (P =.006) in the dialysis group and 1 (P =.002) for that between ferritin and TS in the transplant group. Our results suggest that PTH levels may influence s-TfR levels. Discordance between ferritin, TS, and s-TfR as markers of iron deficiency might be explained by the effects of inflammation.

Serum cystatin C as an index of renal function in kidney transplant patients

Management of renal transplant patients requires periodic measurement of renal function, which is usually assessed by measuring the glomerular filtration rate (GFR). The most commonly used marker for GFR is serum creatinine, although muscle wasting and tubular secretion may lead to overestimation of the actual GFR. Serum concentrations of the low-molecular-weight proteins, cystatin C and beta(2)-microglobulin (B(2)M), may afford useful markers to determine a reduced GFR. We investigated whether these molecules provide reliable indicators of renal function in 75 renal transplant patients. Cystatin C and B(2)M correlated significantly with creatinine (r =.648, P <.05 and r =.578, P <.05, respectively). Inverse serum creatinine was superior to inverse cystatin C and inverse B(2)M when renal function equations were used (r =.95, P <.05, according to MDRD; r =.87, P <.05, according to Cockroft-Gault). Receiver operating characteristic (ROC) analysis was performed to quantitate the accuracy of the different markers to detect reduced GFR using a cutoff value of 70 mL/min. No significant difference between the areas under the ROC curves comparing cystatin C and B(2)M was observed; however, serum creatinine demonstrated a significantly greater value than cystatin C (.981 vs.724, P =.001). We conclude that serum creatinine is a more efficacious marker than serum cystatin C to assess renal function.

Seroprevalence of antibodies to legionella pneumophila in hemodialysis patients

Patients with chronic renal failure are at increased risk for infections because of impaired cellular immunity. This study was designed to determine the prevalence of antibodies to Legionella pneumophila serogroups 1 to 6 and to evaluate the possible risk factors for Legionnaires' disease in hemodialysis patients. Serum samples to be screened for antibodies against L pneumophila and risk factor data were collected from 252 hemodialysis patients. The overall prevalence of L pneumophila antibodies in hemodialysis patients was found to be 5.16% There was no statistically significant difference between L pneumophila seropositivity and potential risk factors. Further studies are needed to determine possible risk factors for Legionnaires' disease in hemodialysis patients.

Evaluation of the new EMIT tacrolimus assay in kidney and liver transplant recipients

Tacrolimus (FK506) is a potent macrolide immunosuppressant used for prevention of organ transplant rejection following transplantation. Monitoring of blood tacrolimus concentrations is essential to assess organ rejection and toxicity, because of the agent's narrow therapeutic range, wide inter- and intraindividual pharmacokinetic variability as well as drug interactions mediated by alteration in cytochrome P450. Several methods have been developed to monitor tacrolimus; immunoassays, bioassays, and HPLC/MS. The purpose of this study was to compare two analytical methods: the well-established MEIA II tacrolimus immunoassay using the IMx analyzer and the new EMIT 2000 tacrolimus immunoassay on the Cobas Integra 400 system. Tacrolimus results obtained using the two methods have been compared on 180 whole blood samples from kidney and liver transplant patients. The analytical sensitivities of both methods were defined as 1.2 ng/mL for EMIT and 1.5 ng/mL for MEIA II. The within-run CVs (n = 15) obtained with four-level controls were 9.08%, 9.41%, 5.23% and 4.4% for EMIT 2000. The comparison showed the following relationship between two methods: MEIA = 1.08.EMIT + 0.20 (r =.893). In conclusion, the EMIT 2000 tacrolimus immunoassay is a reliable alternative for the MEIA II method to monitor tacrolimus in organ transplant recipients. It provides a valid quantitative measurement of tacrolimus with comparable % CVs in quality-control as well as patient blood samples. Additionally, the EMIT 2000 method provides a rapid analysis of a large number of samples in one run with a low turnaround time and possibilities to reanalyze critical samples.

Plasma homocysteine levels in renal transplant patients on tacrolimus therapy

Increased plasma total homocysteine levels afford an independent risk factor to assess cardiovascular morbidity in patients with normal and impaired renal function, including stable transplant recipients. The purpose of this study was to evaluate plasma homocysteine levels and factors known to influence homocysteine metabolism (folate and Vitamin B(12)) in renal transplanted patients treated with tacrolimus. Plasma homocysteine, serum folate and serum vitamin B(12) concentrations were measured in 18 cadaveric renal transplant patients with stable function both before and 3 months after the renal transplantation. While the mean plasma homocysteine level in the renal transplant group was significantly higher than in the control group, no significant change was observed following renal transplantation under tacrolimus therapy (16.84 +/- 6.43 micromol/L vs 16.02 +/- 6.54 micromol/L). The levels of folate before and after transplantation were considerably lower than the control group; a significant effect of tacrolimus has not been observed (7.32 +/- 4.68 ng/mL and 7.55 +/- 5.20 ng/mL). Serum vitamin B(12) levels in the transplant group were significantly lower than the control group; a significant decline was seen 3 months after the renal transplantation (448.94 +/- 230.03 pg/mL vs 334.38 +/- 240.61 pg/mL). Consequently, although plasma homocysteine levels of renal transplant recipients are higher, a lowering effect of tacrolimus therapy was not observed on plasma homocysteine levels. The lower levels of folate and Vitamin B(12) in the transplant group compared to a control group supports therapy with folate and Vitamin B(12) to decrease homocysteine concentrations.

Is there any effect of compliance on clinical parameters of renal transplant recipients?

Noncompliance with regard to diet, medications and routine physician visits is frequently observed among some patient groups. This results in late graft dysfunction and behavior loss. In the present study, we defined compliance as attendance at 80% or more outpatient visits. The study included 63 cadaveric and 158 living-related renal transplant recipients namely, 150 men and 76 women of 8 to 70 years of age (median 38 +/- 12) who were operated between 1986 and 2001. Demographic data, number of visits attended per month, cigarette smoking, and alcohol intake were probed with a questionnaire that was delivered to the patients, 8 of whom died; hemophagocytic syndrome (n = 4), cardiovascular disease (n = 2), Kaposi' sarcoma (n = 1), and cerebrovascular bleeding (n = 1). Twenty-three patients had lost their graft. Compliance among men was lower than among women, a result that trended toward statistical significance (P =.087). Compliance was not related to marital status (P =.297), but tended to increase with educational background (P =.059). Graft loss (P =.546) and aging (P =.509) were not related to compliance. There was no relationship between compliance and mortality rate (P =.526). Interestingly, living-related kidney transplant recipients showed lower compliance than cadaveric kidney recipients, a result that was statistically significant (P =.04). Noncompliance was also related to cigarette smoking during the pre- and posttransplant periods (P =.008 and P =.03, respectively), as well as alcohol intake (P =.000). In conclusion, male gender and living-related donation are related to noncompliance, but (in contrast with literature) not young age, graft loss, or mortality. Compliance increases with educational status of the patients. Smoking and alcohol intake are closely related to noncompliance.

Laparoscopic omental fixation technique versus open surgical placement of peritoneal dialysis catheters

BACKGROUND

Continuous ambulatory peritoneal dialysis (CAPD) is an effective form of treatment for patients with end-stage renal disease. Open insertion of peritoneal dialysis (PD) catheters is the standard surgical technique, but it is associated with a relatively high incidence of catheter outflow obstruction and dialysis leak. Omental wrapping is the most common cause of mechanical problems. The purpose of this study was to determine the efficacy of the laparoscopic omental fixation technique to prevent the obstruction caused by omental wrapping and also to compare this laparoscopic technique with open peritoneal dialysis catheter insertion with respect to postoperative discomfort, complication rates, and catheter survival.

METHODS

Between March 1998 and October 2001, 42 double-cuff, curled-end CAPD catheters were placed in 42 patients. The outcomes of the 21 patients in whom the PD catheters were placed laparoscopically with omental fixation technique were compared with those of the 21 patients in whom the catheters were placed with open surgical technique. Recorded data included patient demographics, catheter implantation method, early and late complications, catheter survival, and catheter outcome.

RESULTS

Early peritonitis episodes occurred in 8 of 21 patients (38.0%) in the open surgical group (OSG) versus 2 of 21 patients (9.5%) in the laparoscopic omental fixation group (LOFG) ( p < 0.05); late peritonitis episodes occurred in 3 of 21 patients (14.2%) in the OSG versus 1 of 21 patients (4.7%) in the LOFG ( p < 0.05). Early exit site infection occurred in 8 of 21 patients (38.0%) in the OSG versus 4 of 21 patients (19.0%) in the LOFG ( p < 0.05), with many catheter-related problems in the conventional surgical group. There was no outflow obstruction in the LOFG. The conventional procedure was faster than the laparoscopic omental fixation technique. Analgesic requirements and hospital stay were less in the laparoscopic group. Laparoscopic surgery also enabled diagnosis of intraabdominal pathologies and treatment of the accompanying surgical problems during the same operation. Occult inguinal hernia was diagnosed in 2 patients, inguinal hernioplasty was performed in 4 patients, adhesiolysis was performed in 8 patients who had previous abdominal surgery, and liver biopsy was taken in 2 patients. Ovarian cystectomy was performed in another patient during laparoscopic CAPD catheter placement.

CONCLUSION

The laparoscopic omental fixation technique (described by Oğünç and published in 1999) is a highly effective and successful method for preventing obstruction due to omental wrapping with a better catheter survival. Laparoscopic surgery also allows the diagnosis and treatment of the accompanying surgical pathologies during the same operation.

Intravenous single-dose tramadol versus meperidine for pain relief in renal colic

BACKGROUND AND OBJECTIVE

Comparison of the effectiveness of tramadol with meperidine given intravenously to emergency patients with suspected renal colic.

METHODS

A double-blind, randomized clinical trial was performed in the Emergency Department of a tertiary-care university hospital. Consecutive patients with suspected renal colic (n = 47) were randomized to receive intravenously an initial dose of tramadol 50 mg (n = 23) or meperidine 50 mg (n = 24). After 30 min, additional doses of meperidine 50 mg were given intravenously as a rescue medication in an open fashion. Pain relief was assessed using a 10 cm visual analogue scale, the primary outcomes being pain relief at 15 and 30 min after the analgesics. Secondary outcomes were the frequency of rescue meperidine use and the development of side-effects.

RESULTS

Visual analogue scale pain scores after 15 and 30 min decreased in both tramadol and meperidine groups (P < 0.05). However, pain relief was better in the meperidine group at the 15 and 30 min evaluations (P < 0.05). Only 11 patients (48%), initially receiving meperidine, needed more meperidine compared with 16 patients (67%) initially receiving tramadol. Both drugs were well tolerated with no adverse effects occurring in either group.

CONCLUSIONS

Meperidine 50 mg was superior to tramadol 50 mg for acute pain relief in patients with suspected renal colic when given intravenously. Because many patients in both groups received supplemental meperidine and the response to tramadol alone cannot be predicted, clinicians may want to choose higher doses of meperidine alone or other alternative combinations.

Bruton tyrosine kinase gene mutations in Turkish patients with presumed X-linked agammaglobulinemia

X-linked agammglobulinemia (XLA) is a ptototypical humoral immunodeficiency caused by mutations in the gene coding for Bruton tyrosine kinase (BTK). The genetic defect in XLA impairs early B cell development resulting in marked reduction of mature B cells in the blood. Studies from different countries have demonstrated that approximately 90% of males with presumed XLA bear mutations in BTK. In this study, we report for the first time the occurrence of BTK mutations in Turkey. We performed mutational analysis of the BTK gene in 16 Turkish male patients from 13 separate families with presumed XLA based on abnormally low peripheral blood B-cell numbers (lt; 1%), hypogammaglobulinemia, and recurrent bacterial infections. We found that in nine of the 13 families (69%) a Btk mutation caused XLA. Two of the mutations were previously described, but seven novel mutations were identified: two missense (Y39C, G584R), one nonsense (Q343X), and 4 deletions (1800-1821del, 1843-1847del, 1288-1292del, 291del) resulting in frameshift and premature stop codon. By contrast, no mutations in the BTK gene were identified in the other 4 families. A consanguinity in three of these families raises the possibility that mutations in other autosomal genes which affect early B cell development may contribute to their phenotype resembling XLA.

Transient hypogammaglobulinemia of infancy: clinical and immunologic features of 40 new cases

BACKGROUND

Transient hypogammaglobulinemia of infancy (THI) results from a delay in the maturation of immunoglobulin production.

METHODS

The clinical and immunologic data of 40 patients with THI are presented. Clinically, the majority of patients presented with recurrent respiratory infections and otitis media, bronchitis and/or bronchial asthma and recurrent gastroenteritis.

RESULTS

Ten of 40 children had isolated low IgG; isolated low IgA and isolated low IgM were detected in one and three patients, respectively. At initial evaluation, levels of all three immunoglobluins were low in nine patients. Ten patients had diminished IgG and IgA levels, six had diminished IgA and IgM levels and one had low IgG and IgM levels. Two patients were given intravenous immunoglobulin replacement therapy for 1 year. None of the patients has experienced serious infections during their follow-up period.

CONCLUSIONS

Prospective evaluation of patients (age range 5-60 months) revealed that immunoglobulin levels in 33 patients recovered before 36 months of age. Seven patients still had low immunoglobluin levels at 40-57 months of age. Three of these patients had low levels of both IgG and IgA, while two patients had low IgM levels and a further two patients had low IgA levels.

Activation-induced cytidine deaminase (AID) deficiency causes the autosomal recessive form of the Hyper-IgM syndrome (HIGM2)

The activation-induced cytidine deaminase (AID) gene, specifically expressed in germinal center B cells in mice, is a member of the cytidine deaminase family. We herein report mutations in the human counterpart of AID in patients with the autosomal recessive form of hyper-IgM syndrome (HIGM2). Three major abnormalities characterize AID deficiency: (1) the absence of immunoglobulin class switch recombination, (2) the lack of immunoglobulin somatic hypermutations, and (3) lymph node hyperplasia caused by the presence of giant germinal centers. The phenotype observed in HIGM2 patients (and in AID-/- mice) demonstrates the absolute requirement for AID in several crucial steps of B cell terminal differentiation necessary for efficient antibody responses.

Mutations in RAB27A cause Griscelli syndrome associated with haemophagocytic syndrome

Griscelli syndrome (GS, MIM 214450), a rare, autosomal recessive disorder, results in pigmentary dilution of the skin and the hair, the presence of large clumps of pigment in hair shafts and an accumulation of melanosomes in melanocytes. Most patients also develop an uncontrolled T-lymphocyte and macrophage activation syndrome (known as haemophagocytic syndrome, HS), leading to death in the absence of bone-marrow transplantation. In contrast, early in life some GS patients show a severe neurological impairment without apparent immune abnormalities. We previously mapped the GS locus to chromosome 15q21 and found a mutation in a gene (MYO5A) encoding a molecular motor in two patients. Further linkage analysis suggested a second gene associated with GS was in the same chromosomal region. Homozygosity mapping in additional families narrowed the candidate region to a 3.1-cM interval between D15S1003 and D15S962. We detected mutations in RAB27A, which lies within this interval, in 16 patients with GS. Unlike MYO5A, the GTP-binding protein RAB27A appears to be involved in the control of the immune system, as all patients with RAB27A mutations, but none with the MYO5A mutation, developed HS. In addition, RAB27A-deficient T cells exhibited reduced cytotoxicity and cytolytic granule exocytosis, whereas MYO5A-defective T cells did not. RAB27A appears to be a key effector of cytotoxic granule exocytosis, a pathway essential for immune homeostasis.

Polymorphism of the fourth component of complement in Turks

An analysis of polymorphism in the fourth component of human complement (C4) was performed on EDTA-plasma from 142 unrelated, randomly selected Turks without collagen-vascular disease or recurrent infections. Plasma samples treated with neuraminidase and carboxypeptidase-B were subjected to high-voltage agarose gel electrophoresis followed by immunofixation. C4B allotypes were further detected in some samples by Western blots with monoclonal antibody 1228 (anti-C4B/Ch1 reactivity). The frequencies of C4A and C4B alleles were determined. Allele C4B*5, which has been found to be relatively common in Asian (Oriental) populations, was not detected in this study. No specific predilection could be noted among the rare variants. C4A*3-C4B*1 was the most common haplotype (n = 40/142, or 28%) but was found less frequently than in Caucasian populations. This finding may be the result of the limited number of samples examined. C4A and/or C4B null allotypes were seen in 49 of 142 (34.6%) subjects. The most frequent C4 null allotype seen was C4B null (37/142, or 26%): 28 subjects had one C4B null allele; 1 had a homozygous deficiency of C4B (C4B*QO, *QO) and 7 had C4A*QO C4B*QO, a double heterozygous haplotype. Frequencies of homozygous haplotype C4A*Q0-C4B*Q0 in the population studied were found to be 0.007. The results of this study demonstrate that the genetic composition of the Turkish population exhibits both similarities and differences with the European population, and ranges between Caucasian and Mongoloid (Asian) populations.

Isolated cutaneous response to granulocyte-monocyte colony stimulating factor in fatal idiopathic disseminated Bacillus-Calmette-Guerin infection

Severe disseminated Bacillus-Calmette-Guerin (BCG) infection is very rare and has been regarded as idiopathic when no immunodeficiency is present. This entity seems to be due to several new types of inherited abnormalities in the pathways important in defence against Mycobacteria. Although improvement with interferon-gamma (IFN-gamma) has been reported in some patients, to our knowledge there are no reports on the effect of other cytokines in the treatment of these patients. We report here the clinical response to IFN-gamma and granulocyte-monocyte colony stimulating factor (GM-CSF) treatment in a patient with idiopathic disseminated BCG infection who failed to respond to multiple antimycobacterial agents. The patient showed partial and transitory response to IFN-gamma, however, GM-CSF treatment led to rapid improvement of skin lesions within 2 weeks without any effect on the progression of the disease in the other organ systems.

CONCLUSION

The response of idiopathic disseminated Bacillus-Calmette-Guerin infection to granulocyte-monocyte colony stimulating factor treatment was limited to cutaneous lesions. Granulocyte-monocyte colony stimulating factor may have acted to promote wound healing or the levels of this factor achieved in other affected organs may have been inadequate.

Two genes are responsible for Griscelli syndrome at the same 15q21 locus

Griscelli syndrome is a rare autosomal recessive disease characterized by pigment dilution, variable cellular immunodeficiency, and an acute phase of uncontrolled T lymphocyte and macrophage activation. We previously mapped the disease locus to 15q21 and showed that a MyoVa gene (HGMW-approved symbol MYO5A) defect leads to Griscelli syndrome. We report a second MyoVa mutation in a new patient, confirming this first finding. However, in four other Griscelli syndrome patients analyzed, the MYOVA protein is expressed, and no mutation can be detected in the MyoVa gene coding sequence, even in the alternatively spliced region for which exon-intron boundaries were characterized. Linkage analysis performed in 15 Griscelli families thus far studied confirms the first localization. However, fine haplotype analysis in three families strongly suggests the existence of a second gene at the same locus for Griscelli syndrome less than 7.3 cM distant from the MyoVa gene.

Cyclic neutropenia complicated by renal AA amyloidosis

Cyclic neutropenia is a rare disease characterized by regular cyclic fluctuations in the numbers of neutrophils. Patients with the disease suffer from recurrent infections at regular intervals of nearly three weeks. Recently, recombinant human granulocyte colony-stimulating factor (rhG-CSF) was reported to be an effective treatment for this disease. here we describe 17-year-old cyclic neutropenic female patient with a very rare association of renal amyloidosis of AA type who was under intermittent rhG-CSF treatment for the previous one and a half years. We conclude that although the disorder is usually benign, reactive amyloidosis may rarely develop in cases who remain untreated for a long period of time. However familial Mediterranean fever (FMF) type II should also be born in mind, particularly in predisposed populations.

Mutations in Igalpha (CD79a) result in a complete block in B-cell development

Mutations in Btk, mu heavy chain, or the surrogate light chain account for 85-90% of patients with early onset hypogammaglobulinemia and absent B cells. The nature of the defect in the remaining patients is unknown. We screened 25 such patients for mutations in genes encoding components of the pre-B-cell receptor (pre-BCR) complex. A 2-year-old girl was found to have a homozygous splice defect in Igalpha, a transmembrane protein that forms part of the Igalpha/Igbeta signal-transduction module of the pre-BCR. Studies in mice suggest that the Igbeta component of the pre-BCR influences V-DJ rearrangement before cell-surface expression of mu heavy chain. To determine whether Igalpha plays a similar role, we compared B-cell development in an Igalpha-deficient patient with that seen in a mu heavy chain-deficient patient. By immunofluorescence, both patients had a complete block in B-cell development at the pro-B to pre-B transition; both patients also had an equivalent number and diversity of rearranged V-DJ sequences. These results indicate that mutations in Igalpha can be a cause of agammaglobulinemia. Furthermore, they suggest that Igalpha does not play a critical role in B-cell development until it is expressed, along with mu heavy chain, as part of the pre-BCR.

Successful bone marrow transplantation in a case of Griscelli disease which presented in accelerated phase with neurological involvement

Griscelli disease (GD) is a rare disorder characterized by pigment dilution, immunodeficiency and occurrence of accelerated phase consisting of hemophagocytosis, pancytopenia and neurological manifestations. Allogeneic BMT in the early period is an important modality of treatment for GD. We carried out an alloBMT from an HLA-identical sibling donor on a 4-year-old girl who presented in accelerated phase with neurological manifestations including convulsions, strabismus, severe dysarthria, ataxia and clonus. She was treated with etoposide, methylprednisolone and intrathecal methotrexate for 8 weeks and underwent alloBMT after receiving a conditioning regimen including ATG (rabbit, 10 mg/kg x 5 days), Bu/Cy. 8 x 108/kg nucleated bone marrow cells were given. Engraftment occurred early and the post-BMT period was uneventful. Currently, she is at 18 months post BMT with sustained engraftment and with a normal neurological examination except for minimal clonus. Long-term follow-up will determine the prognosis regarding the neurological findings.

Altered apoptotic profiles in irradiated patients with increased toxicity

PURPOSE

A retrospective study of radiation-induced apoptosis in CD4 and CD8 T-lymphocytes, from 12 cancer patients who displayed enhanced toxicity to radiation therapy and 9 ataxia telangiectasia patients, was performed to test for altered response compared to healthy blood-donors and normal cancer patients.

METHODS AND MATERIALS

Three milliliters of heparinized blood from each donor was sent via express post to the Paul Scherrer Institute (PSI) for subsequent examination. The blood was diluted 1:10 in RPMI medium, irradiated with 0-, 2-, or 9-Gy X-rays, and incubated for 48 h. CD4 and CD8 T-lymphocytes were then labeled using FITC-conjugated antibodies, erythrocytes were lysed, and the DNA stained with propidium iodide. Subsequently, cells were analyzed using a Becton Dickinson FACScan flow cytometer. Radiation-induced apoptosis was recognized in leukocytes as reduced DNA content attributed to apoptosis-associated changes in chromatin structure. Apoptosis was confirmed by light microscopy, electron microscopy, and by the use of commercially available apoptosis detection kits (in situ nick translation and Annexin V). Data from hypersensitive individuals were compared to a standard database of 105 healthy blood-donors, and a database of 48 cancer patient blood donors who displayed normal toxicity to radiation therapy. To integrate radiosensitivity results from CD4 and CD8 T-lymphocytes after 2 and 9 Gy, z-score analyses were performed.

RESULTS

A cohort of 12 hypersensitive patients was evaluated; 8 showed enhanced early toxicity, 3 showed enhanced late toxicity, and 1 showed both. The cohort displayed less radiation-induced apoptosis (-1.8 sigma) than average age-matched donors. A cohort of 9 ataxia telangiectasia homozygotes displayed even less apoptosis (-3.6 sigma).

CONCLUSION

The leukocyte apoptosis assay appears to be a useful predictor of individuals likely to display increased toxicity to radiation therapy; however, validation of this requires a prospective study.

Impaired IgG antibody production to pneumococcal polysaccharides in patients with ataxia-telangiectasia

Various factors seem to be etiologic in the susceptibility to sinopulmonary infections in ataxia-telangiectasia (A-T) patients, i.e., low serum and salivary IgA, low serum IgG2, and even aspiration of saliva. S. pneumoniae is a common pathogen responsible from pulmonary infections and impaired antibody response to polysaccharide antigens is seen in patients with IgG2 and IgA deficiency as well as patients with CVID and WAS. We studied IgG-type antibody production to six pneumococcal serotypes in 29 A-T patients by ELISA before and 3-4 weeks after pneumococcal vaccine. The response was considered positive when the antibody titer was >10 U/ml but weak when the titer was 10-20 U/ml. Twenty-two of 29 (76%) patients did not respond to any of the serotypes, 5 (17%) showed a positive response to one serotype, 1 (3.4%) to two serotypes, and 1 (3.4%) to four serotypes. With conversion to gravimetric units (ng IgG/ml) and >1800 ng/ml (300 ng Ab N/ml) considered a positive response, 5 of 29 (17.2%) patients showed a positive response (300 ng ab N/ml) to two or fewer serotypes. All patients tested produced IgG antibody to tetanus toxoid. Sixteen of 27 (59.3%) patients had low IgG2 and four (14.8%) had low IgG3 levels, while 18 (62.1%) of 29 patients had low serum IgA. No correlation was found either between serum Ig isotype levels and antipolysaccharide antibody response or between susceptibility to infection and antibody production. The mechanism responsible for disturbed antipolysaccharide (TI-2 antigen) antibody production in patients with A-T needs to be investigated. It may provide additional information on the function of the ATM gene product and be helpful in clarifying the role of B cells and contribution of T cells in TI-2 responses.

Alopecia universalis in a patient with common variable immunodeficiency

A 12-year-old boy with common variable immunodeficiency (CVI) who developed severe alopecia is presented. His sister also had alopecia and recurrent infections and died of lung infection at the age of 7 years. The loss of hair in both children was total; the pathology of a scalp skin biopsy specimen was typical for alopecia areata. The boy was subjected to clinical and immunologic evaluation and the results were compatible with common variable immunodeficiency.

Gastric antral stricture in a patient with chronic granulomatous disease

Chronic granulomatous disease (CGD) is a rare disorder of phagocytic cell oxidative metabolism. Patients have recurrent infections with catalase-positive organisms and granulomatous lesions throughout the body. Gastric antrum can be an occult site of involvement. We describe a four-year old boy with chronic granulomatous disease who was admitted with the complaints of persistent vomiting and weight loss. Gastric antral narrowing was diagnosed according to radiological findings. Treatment with steroid and antibiotics yielded a good clinical response in 15 days with a relief of the obstruction. This case report emphasizes the beneficial effect of this form of therapy in preventing life-threatening obstruction of vital organs in CGD.

Congenital erythropoietic porphyria successfully treated by allogeneic bone marrow transplantation

The long-term biochemical and clinical effectiveness of allogenic bone marrow transplantation (BMT) was shown in a severely affected, transfusion-dependent 18-month-old female with congenital erythropoietic porphyria (CEP), an autosomal recessive inborn error of heme biosynthesis resulting from mutations in the uroporphyrinogen III synthase (URO-synthase) gene. Three years post-BMT, the recipient had normal hemoglobin, markedly reduced urinary porphyrin excretion, and no cutaneous lesions with unlimited exposure to sunlight. The patient was homoallelic for a novel URO-synthase missense mutation, G188R, that expressed less than 5% of mean normal activity in Escherichia coli, consistent with her transfusion dependency. Because the clinical severity of CEP is highly variable, ranging from nonimmune hydrops fetalis to milder, later onset forms with only cutaneous lesions, the importance of genotyping newly diagnosed infants to select severely affected patients for BMT is emphasized. In addition, the long-term effectiveness of BMT in this patient provides the rationale for future hematopoietic stem cell gene therapy in severely affected patients with CEP.

Restructuring the primary health care services and changing profile of family physicians in Turkey

A new health-reform process has been initiated by Ministry of Health in Turkey. The aim of that reform is to improve the health status of the Turkish population and to provide health care to all citizens in an efficient and equitable manner. The restructuring of the current health system will allow more funds to be allocated to primary and preventive care and will create a managed market for secondary and tertiary care. In this article, we review the current and proposed primary care services models and the role of family physicians therein.

Fc gamma receptor allotypes in children with bacterial meningitis. A preliminary study

IgG2 antibody is the essential subclass to protect against encapsulated bacteria Fc gamma RIIa is the only Fc gamma receptor that interacts with human IgG2. The two genetically determined allotypes of human Fc gamma RIIa, Fc gamma RIIa-R131 and Fc gamma RIIa-H131 alleles have functionally different reactivities with IgG2 in vitro, and H/H-131 cells have markedly higher binding affinity for human IgG2. Homozygous Fc gamma RIIIb-NA1/NA1 PMNLs show higher phagocytic capacity than Fc gamma RIIIb-NA2/NA2 PMNLs. To evaluate in vivo significance of Fc gamma RIIa and Fc gamma RIIIb allotypes, we analyzed Fc gamma R allotypes in children with bacterial meningitis due to Haemophilus influenzae type b, Streptococcus pneumoniae and Neisseria meningitidis. Fc gamma RII and Fc gamma RIIIb polymorphisms were determined by using quantitative flow cytometry. Fc gamma RIIa were studied in 23 children with bacterial meningitis and 50 healthy Turkish controls, and Fc gamma IIIb in 18 and 43 such individuals, respectively. The distribution of Fc gamma RIIa in the healthy Turkish control group was found to be significantly different from that in the Chinese and Japanese population (p < 0.05), but similar to that of the white population in the USA and the Netherlands. No case (0%) had the Fc gamma RII-H/H-131 Fc gamma RIIIb-NA1/NA1 the corresponding figure in the controls was 4 (9.3%). Homozygous Fc gamma RIIa-H/H-131 phenotype was underrepresented with borderline significance (p: 0.057) in patients below two years of age in comparison with the healthy subjects and with patients with meningitis over two years of age (p: 0.059). Although the study needs to be conducted in a large series of patients in order to draw a firm conclusion, Fc gamma RIIa polymorphism may be a contributing factor to the increased susceptibility to meningitis with encapsulated bacteria in children below two years of age.

Allogeneic bone marrow transplantation in Fanconi anemia from Turkey: a report of four cases

Bone marrow transplantation (BMT) is currently the treatment of choice for patients with Fanconi anemia (FA) if a suitable donor is available. Four children with FA underwent allogeneic BMT from HLA-identical siblings during the period from 1995 to 1996. Pretransplant conditioning was Cyclophosphamide (Cy) (20 mg/kg) + Thoracoabdominal irradiation (TAI) (500 cGy) +/- Antithymocyte globulin (ATG) (2 mg/kg/day x 3). Cyclosporin A (CsA) was used as GvHD prophylaxis. The time of neutrophil (ANC>500) and platelet (>50,000) recovery were at 11-14 and 17-25 days, respectively. One patient with a pretransplant history of multiple transfusions experienced graft rejection and died at day +29 with infection and bleeding. Although three patients sustained engraftment one developed donor originated acute lymphoblastic leukemia (ALL) 18 months after BMT and died with CNS hemorrhage and infection at +25 months following 7 months of chemotherapy. None of the patients developed grade 3-4 acute GvHD. Cytotoxicity included grade II mucositis in all and severe gastroenteritis in one patient. During a follow-up period of 10 months and 2 years, two patients are well with normal blood count, recovering immune function and have a Karnofsky score of 90%.

A case of chronic severe neutropenia: oral findings and consequences of short-term granulocyte colony-stimulating factor treatment

Neutropenia is an absolute decrease in the number of circulating neutrophils in the blood which results in susceptibility to severe pyogenic infections. Various oral findings such as periodontitis, alveolar bone loss and ulceration may be seen in neutropenic patients. A case is presented of a 6 year old girl with chronic, probably congenital, severe neutropenia with frequent respiratory tract infections, recurrent oral ulcerations and significant periodontal break-down resembling prepubertal periodontitis. She was given granulocyte-colony stimulating factor (G-CSF) treatment which resulted in an increase in granulocyte count within two weeks and resolution of the neutropenic ulceration. It is suggested that G-CSF together with dental care regimens is a promising treatment model in chronic severe neutropenia cases presenting with oral manifestations.

Defective serum opsonization activity in children aged 6-48 months having acute purulent otitis media

Serum opsonization of yeast (Saccharomyces) was investigated in 51 patients whose ages were between six and 48 months (median 15 months) with acute purulent otitis media and in an age-matched control group (median 13 months). Opsonization was assessed by measuring yeast particle uptake in an assay based on an electronic count of the unphagocytosed particles in serum by polymorphonuclear leukocytes. Despite normal levels of CH50 and serum immunoglobulins, a defective opsonization was determined in 13.7 percent of the patients (7 in 51). The corresponding figure was 2.9 percent in 103 healthy controls (p < 0.001). On the other hand, 218 percent (5 in 23) of the children having a history of recurrent purulent otitis media showed defective opsonization (p < 0.001). Previously, the presence of an opsonization defect has been linked to low levels of mannan binding lectin (MBL), a calcium dependent serum lectin that acts as an opsonin. Therefore, our findings indirectly support the idea that MBL has an important role as host defense, particularly in the earlier period of life when the antibody repertoire is restricted.

Development of systemic lupus erythematosus in a patient with selective complete C1q deficiency

A 7-year-old male with recurrent erythematous and desquamated skin lesions and respiratory infections was diagnosed as selective complete C1q deficiency following detailed studies of the complement system. His asymptomatic sister also had selective complete C1q deficiency. During a follow up period of 3 years, his skin lesions persisted, he suffered from recurrent bronchopneumonias and glomerulonephritis developed. Renal function deteriorated with the appearance of anti-DNA antibodies. Renal biopsy was consistent with systemic lupus erythematosus. The patient was treated with immunosuppressive drugs, but died of renal failure. It is postulated that in this patient defective clearance of antigen-antibody complexes by the reticulo-endothelial system resulted in progressive renal disease as observed in other complement deficiencies. A retrospective molecular study disclosed a point mutation in the ClqA chain gene in a heterozygous state in parents and two siblings; in a homozygous state in the asymptomatic sister. The reason why some individuals with this defect are asymptomatic is not known at present. Diagnosis of heterozygotes by molecular studies is extremely important to give genetic counselling to the family.

CONCLUSION

Patients with recurrent infections, erythematous desquamative skin lesions, malar rash and oral mucosal involvement should be screened for complement C1q deficiency.

Dyskeratosis congenita: unusual onset with isolated neutropenia at an early age

A 3.5 year old male patient with dyskeratosis congenita (DC) presented at the age of 13 months with isolated neutropenia preceding characteristic skin findings. The average absolute neutrophil count of 500/mm3 persisted without the presence of anemia or thrombocytopenia during the follow up. Neutropenia responded to granulocyte-colony stimulating factor (G-CSF) at a dose of 10 micrograms/kg per day. Immunologic findings were normal as was the chromosomal stability and sister chromatid exchange.