Wildfire particulate exposure and risks of preterm birth and low birth weight in the Southwestern United States.

OBJECTIVES: Wildfire air pollution is a growing concern on human health. The study aims to assess the associations between wildfire air pollution and pregnancy outcomes in the Southwestern United States. STUDY DESIGN: This was a retrospective cohort study. METHODS: Birth records of 627,404 singleton deliveries in 2018 were obtained in eight states of the Southwestern United States and were linked to wildfire-sourced fine particulate matter (PM2.5) and their constituents (black carbon [BC] and organic carbon [OC]) during the entire gestational period. A double-robust logistic regression model was used to assess the associations of wildfire-sourced PM2.5 exposures and preterm birth and term low birth weight, adjusting for non-fire-sourced PM2.5 exposure and individual- and area-level confounder variables. RESULTS: Wildfire-sourced PM2.5 contributed on average 15% of the ambient total PM2.5 concentrations. For preterm birth, the strongest association was observed in the second trimester (odds ratio [OR]: 1.06, 95% confidence interval [CI]: 1.05-1.07 for PM2.5; 1.06, 95% CI: 1.05-1.07 for BC; 1.04, 95% CI: 1.03-1.05 for OC, per interquartile range increment of exposure), with higher risks identified among non-smokers or those with low socio-economic status. For term low birth weight, the associations with wildfire-sourced PM2.5 exposures were consistently elevated for all trimesters except for the exposure averaged over the entire gestational period. Overall, the associations between wildfire-sourced PM2.5 and pregnancy outcomes were stronger than those with total PM2.5. CONCLUSIONS: Wildfire-sourced PM2.5 and its constituents are linked to higher risks of preterm birth and term low birth weight among a significant US population than the effects of ambient total PM2.5.

[Maternal periconceptional folic acid supplementation and its effects on the prevalence of fetal neural tube defects].

OBJECTIVE: To find out the status of folic acid supplementation among women, to evaluate the prevention effects on neural tube defects (NTDs), and to explore the factors impact on folic acid supplementation compliance. METHODS: Based on the routine data of 92 121 women in prenatal health care and birth defect surveillance system in Tongzhou District of Beijing from 2013 to 2018, we described the prevalence of periconceptional folic acid supplementation, pre-pregnancy folic acid supplementation and regularly folic acid supplementation (compliance supplementation). Trend χ2 tests were used to evaluate the change of folic acid supplementation prevalence. The prevalence difference among the women with folic acid supplementation and without supplementation were tested with Fisher's exact test. Factors asso-ciated with folic acid supplementation compliance rate were analyzed with univariate and multivariate Logistic regression model. RESULTS: The prevalence of periconceptional folic acid supplementation during the six years was 90.08% and it was increased from 2013 to 2018, but the rate of pre-pregnancy and regular supplementation was only 41.5% and declined from 2013 to 2018, especially 2013 to 2015. The prevalence of NTDs among the fetuses whose mothers took folic acid during periconceptional period was 5.5/10 000, while the prevalence for the fetuses whose mothers did not take folic acid was 19.7/10 000 (P < 0.001), the rates ratio was 27.9% (χ2=23.74, P < 0.001). The difference between the prevalence of NTDs among the fetuses whose mothers took folic acid only and multiple micronutrients was not statistically significant. After controlling the confounding factors, it was found that the compliant folic acid supplementation rates in women, whose household registrations were outside Beijing and whose education levels were junior high school or below, and who were younger than 25 years old, and who were multiparas and who were pre-pregnancy underweight or obese, were lower than those of the corresponding control groups (P < 0.05). CONCLUSION: The rate of folic acid supplementation among women in Tongzhou District of Beijing was relatively high, but their compliance was poor. Women who did not take folic acid during periconception seriously affected the prevention effect of NTDs. We should focus on women who are younger than 25 years old, lower educated, pre-pregnancy underweight or obese, multiparas and nonlocal household registers, in order to improve the periconceptional folic acid supplementation compliance and improve the effects of NTDs prevention.

An unusual case of both upper and lower gastrointestinal bleeding in a kidney transplant recipient.

BACKGROUND: Tuberculosis (TB) is an uncommon opportunistic infection in immunocompromised patients. Extrapulmonary infection involving the intestine is rare and poses diagnostic difficulties. CASE REPORT: A 49-year-old man with IgA nephropathy underwent a kidney transplantation in 1996 and was put on cyclosporine, azathioprine, and steroid. He suffered from a recurrence of his primary kidney disease and had a gradual deterioration of renal function since 1998. By 2005, he presented with an unusual gastrointestinal (GI) symptom with alternating signs of upper GI bleeding - melena - as well as lower GI bleeding with fresh rectal bleeding, resulting in severe anemia with hemoglobin level down to 5.0 g/dL. At the same time, his renal function further deteriorated and necessitated the initiation of dialysis while he was maintained on low-dose immunosuppressive drugs. Repeated upper and lower GI endoscopies were either unremarkable or revealed non-specific lesions. Symptoms persisted and exploratory laparotomy finally showed a 1 cm submucosal mass at the proximal jejunum and multiple inflammatory lesions at the terminal ileum. Segmental resection of the lesions was performed and confirmed TB infection. However, despite the initiation of anti-tuberculous treatment, the patient eventually died of complications. CONCLUSION: Diagnosing TB intestinal infection is a clinical challenge. A high index of suspicion in susceptible subjects is necessary, and early surgical intervention should always be considered when facing diagnostic uncertainties.

Acute renal failure associated with prolonged intake of slimming pills containing anthraquinones.

Chinese herbal medicine preparations are widely available and often regarded by the public as natural and safe remedies for a variety of medical conditions. Nephropathy caused by Chinese herbs has previously been reported, usually involving the use of aristolochic acids. We report a 23-year-old woman who developed acute renal failure following prolonged use of a proprietary Chinese herbal slimming pill that contained anthraquinone derivatives, extracted from Rhizoma Rhei (rhubarb). The renal injury was probably aggravated by the concomitant intake of a non-steroidal anti-inflammatory drug, diclofenac. Renal pathology was that of hypocellular interstitial fibrosis. Spontaneous renal recovery occurred upon cessation of the slimming pills, but mild interstitial fibrosis and tubular atrophy was still evident histologically 4 months later. Although a causal relationship between the use of an anthraquinone-containing herbal agent and renal injury remains to be proven, phytotherapy-associated interstitial nephropathy should be considered in patients who present with unexplained renal failure.

Very long-chain acyl-CoA dehydrogenase deficiency presenting as acute hypercapnic respiratory failure.

Very long-chain acyl-CoA dehydrogenase deficiency (VLCAD) is a key enzyme catalysing the dehydrogenation of long-chain fatty acids in mitochondrial beta-oxidation. VLCAD deficiency is a genetic disorder that commonly presents in infancy or childhood with episodes of hypoketotic hypoglycaemia, cardiomyopathy and liver dysfunction. The present study reports an 18-yr-old Chinese female who presented with acute hypercapnic respiratory failure and rhabdomyolysis after a period of prolonged fasting and exertion. VLCAD deficiency was confirmed with decreased VLCAD activity in cultured fibroblasts. The patient completely recovered with supportive care. Pulmonary function tests after the acute episode showed evidence of chronic subclinical respiratory muscle weakness. In conclusion, this rare metabolic disorder should be considered in patients presenting with unexplained acute respiratory paralysis and failure.

Disseminated strongyloidiasis: a retrospective study of clinical course and outcome.

A retrospective study was carried out to evaluate the clinical course and outcome of disseminated strongyloidiasis treated in a regional hospital in Hong Kong over a 10-year period. Seven cases were identified, and the case history of each patient was analysed. The most common presenting symptom was fever (100%). Five (71%) patients had gastrointestinal symptoms, the most common being abdominal pain and diarrhoea. Three (42%) patients had a significant drop in haemoglobin. Six (85%) patients had bronchoalveolar infiltrates on chest radiographs. Most patients were immunosuppressed by means of steroid treatment for their underlying primary disease. One patient was diabetic, and another had lymphoma and was receiving chemotherapy. Strongyloides larvae were identified in stool specimens in two patients, in sputum smears in two patients, and in gastric biopsies in three patients. Five (71%) of the patients with lung involvement progressed to respiratory failure and died. Two (29%) cases were complicated by gram-negative bacterial infection. No patient had eosinophilia on presentation. All patients received antihelminthic treatment of variable duration. The case fatality rate in the cohort was 71% despite aggressive supportive therapy. Pulmonary and bowel symptoms were prominent in our series. In conclusion, the diagnosis of disseminated strongyloidiasis is often delayed because of nonspecific presenting symptoms. Early diagnosis relies on a high index of clinical suspicion, especially in immunocompromised hosts. Screening for Strongyloides infection before the initiation of immunosuppressive therapy should be considered, especially in endemic areas.

Mycobacterium chelonae exit site infection in a patient on peritoneal dialysis.

Atypical mycobacterial infe tion of the Tenckhoff catheter exit site is rare. Eradication of the infection is often difficult without the removal of the Tenckhoff cath ter. We report here a case of Mycobacterium chelonae exit site infection in a peritoneal dialysis patient. He was treated with a combination regimen of prolonged antibiotics, local heat therapy, deroofing and shaving of the Tenckhoff catheter outer cuff. This resulted in the successful treatment of the infection without the need for removal of the Tenckhoff catheter. We recommend that this therapeutic approach could be considered in similar cases and that removal of Tenckhoff catheter is not mandatory.

Acute renal failure related to intravenous immunoglobulin infusion in an elderly woman.

Intravenous immunoglobulin infusion induces acute renal failure via a mechanism of osmotic nephrosis. Most reported cases are related to the use of sucrose-based intravenous immunoglobulin. Maltose-based intravenous immunoglobulin is thought to be a safer alternative and have a lower risk of renal toxicity than sucrose-based preparations. Maltase, but not sucrase, is present in the brush border of proximal convoluted renal tubules, where the maltose is metabolised. We report a case of maltose-based intravenous immunoglobulin-induced acute renal failure in an elderly diabetic woman. In this case, the risk factors included advanced age, hypovolaemia, sepsis, diabetes mellitus, and the high infusion rate of the intravenous immunoglobulin. Maltase is readily inhibited by hyperglycaemia; therefore, poor glycaemic control may predispose patients to develop acute renal failure even with the better-tolerated maltose-based intravenous immunoglobulin.

Successful kidney re-transplantation in a patient with previous allograft kidney tuberculosis.

Opportunistic infections, and in particular tuberculosis (TB), carry substantial morbidity and mortality in solid organ transplant recipients. We report a 39-year-old man who underwent a cadaveric renal transplant. Three months postoperatively, he was diagnosed to have tuberculous infection of his graft kidney manifested as fever and renal impairment. The diagnosis was confirmed by renal biopsy, which showed granuloma formation and positive stain for acid-fast bacilli (AFB). His systemic symptoms responded well to a complete course of anti-tuberculous therapy, but his renal function continued to deteriorate. Graft nephrectomy was performed and the patient underwent a second kidney transplant 1 year later. He remained well and asymptomatic thereafter. No signs of recurrence of tuberculous infection were noted up until the present time. This case illustrates that TB remains an important threat to transplant recipients. Although reactivation of dormant TB is the usual mode of infection, acquisition from the donor graft is also possible. The latter may account for the infection in our case, as our patient had a negative tuberculin skin test and normal chest radiograph prior to transplant. The identification of AFB in the kidney graft less than 3 months postoperatively also suggested that causal relationship. While diagnosing TB in post-transplant recipients is difficult and may require renal biopsy, as in our case, treatment on the other hand is no different from the standard protocols. However, no consensus has been reached on the safety of re-transplantation. Also, the need for graft nephrectomy and chemoprophylaxis remains unclear.

Treatment of vancomycin-intermediate Staphylcoccus aureus endocarditis with linezolid.

We report a case of infective endocarditis due to vancomycin-intermediate Staphylococcus aureus that developed after repeated courses of vancomycin. The patient had underlying end stage renal disease and dissecting aortic aneurysm with aortic graft and prosthetic aortic valve replacement. He responded to prolonged combination therapy with linezolid and amikacin without undergoing surgical intervention.

Misplacement of a right internal jugular vein haemodialysis catheter into the mediastinum.

A 69-year-old woman with end-stage renal failure discontinued continuous ambulatory peritoneal dialysis and commenced temporary haemodialysis because of resistant peritonitis. Right internal jugular vein haemodialysis catheter placement was performed. The cuffed, tunnelled haemodialysis catheter was inserted using the modified Seldinger technique. When haemodialysis was initiated the following day, blood could not be aspirated from the catheter and the patient complained of central chest pain during the aspiration. Subsequent venography and computed tomography scan of the thorax showed that the catheter was placed extraluminally into the posterior mediastinum. The importance of a chest radiograph after placement of a central venous catheter is highlighted by this case report. Subtle deviations in catheter position from normal should alert the physician to the possibility of catheter misplacement and lead to further investigation.

Effect of low molecular weight heparin on bone metabolism and hyperlipidemia in patients on maintenance hemodialysis.

The effect of low molecular weight heparin (LMWH) on serum lipid profile in hemodialysis remains controversial and its effect on bone metabolism has not been studied. A crossover study was conducted in 40 patients on stable hemodialysis using unfractionated heparin (UFH) for more than 24 months. These patients were then treated with a LMWH (nadroparin-Ca) for 8 months during hemodialysis and subsequently switched back to UFH for 12 months. Serum lipid profile, biochemical markers for bone metabolism, and bone densitometry (BMD) were monitored at four-month intervals while all medications remained unchanged. Cholesterol (TC), triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C), lipoprotein(a) (Lp(a)), apolipoprotein B (Apo B) were raised in 35%, 29%, 12%, 24% and 24% of patients respectively. High-density lipoprotein-cholesterol (HDL-C) and apolipoprotein A1 (Apo A-1) were reduced in 47% and 9% of patients. Bone-specific alkaline phosphatase (BALP) and intact osteocalcin (OSC), both reflecting osteoblastic activity, were raised in 65% and 94% of patients. Tartrate-resistant acid phosphatase (TRACP) reflecting osteoclastic activity and parathyroid hormone (PTH) were elevated in 35% and 88% of patients. Following LMWH treatment, TC, Tg, Lp(a) and Apo B were reduced by 7%, 30%, 21% and 10% respectively (p<0.05 or <0.01) while Apo A-1 were raised by 7% (p<0.01). Simultaneously, TRACP was reduced by 13% (p<0.05). These biochemical changes were detected soon after 4 months of LMWH administration. Although BMD values in our patients were lower than those of age-matched normal subjects, significant changes were not observed with LMWH treatment. After switching back to UFH for hemodialysis, these biochemical indices reverted to previous values during UFH treatment with a significant higher level in TC and Apo B while serum Apo A-1 remained elevated. Our study suggests LMWH may partially alleviate hyperlipidemia and, perhaps, osteoporosis associated with UFH administration in patients on maintenance hemodialysis.

Efficacy of mycophenolate mofetil in patients with diffuse proliferative lupus nephritis. Hong Kong-Guangzhou Nephrology Study Group.

BACKGROUND: The combination of cyclophosphamide and prednisolone is effective for the treatment of severe lupus nephritis but has serious adverse effects. Whether mycophenolate mofetil can be substituted for cyclophosphamide is not known. METHODS: In 42 patients with diffuse proliferative lupus nephritis we compared the efficacy and side effects of a regimen of prednisolone and mycophenolate mofetil given for 12 months with those of a regimen of prednisolone and cyclophosphamide given for 6 months, followed by prednisolone and azathioprine for 6 months. Complete remission was defined as a value for urinary protein excretion that was less than 0.3 g per 24 hours, with normal urinary sediment, a normal serum albumin concentration, and values for serum creatinine and creatinine clearance that were no more than 15 percent above the base-line values. Partial remission was defined as a value for urinary protein excretion that was between 0.3 and 2.9 g per 24 hours, with a serum albumin concentration of at least 30 g per liter. RESULTS: Eighty-one percent of the 21 patients treated with mycophenolate mofetil and prednisolone (group 1) had a complete remission, and 14 percent had a partial remission, as compared with 76 percent and 14 percent, respectively, of the 21 patients treated with cyclophosphamide and prednisolone followed by azathioprine and prednisolone (group 2). The improvements in the degree of proteinuria and the serum albumin and creatinine concentrations were similar in the two groups. One patient in each group discontinued treatment because of side effects. Infections were noted in 19 percent of the patients in group 1 and in 33 percent of those in group 2 (P = 0.29). Other adverse effects occurred only in group 2; they included amenorrhea (in 23 percent of the patients), hair loss (19 percent), leukopenia (10 percent), and death (10 percent). The rates of relapse were 15 percent and 11 percent, respectively. CONCLUSIONS: For the treatment of diffuse proliferative lupus nephritis, the combination of mycophenolate mofetil and prednisolone is as effective as a regimen of cyclophosphamide and prednisolone followed by azathioprine and prednisolone but is less toxic.

Intraperitoneal pulse calcitriol in the treatment of secondary hyperparathyroidism in patients on continuous ambulatory peritoneal dialysis.

OBJECTIVE: To determine whether it is practicable to use intraperitoneal calcitriol to treat continuous ambulatory peritoneal dialysis (CAPD) patients with secondary hyperparathyroidism and whether this form of therapy is effective and safe. DESIGN: A prospective, nonrandomized study. SETTING: Division of Nephrology, Tertiary Hospital. METHOD: Eight patients from our CAPD population were recruited (5 F, 3 M), aged 24 to 63 years (mean 38.9 +/- 7.6 yr). They had been on CAPD for 8 to 84 months (mean 47.6 +/- 24.6 months). All the patients had bone biopsy-proven secondary hyperparathyroidism with 2 patients showing mixed lesions. The CAPD system was changed to the twin-bag system (Ultrabag, Baxter Healthcare, McGaw Park, IL, U.S.A.) in all 8 patients, who were taught to inject the calcitriol directly through the short transfer set and the Tenckhoff catheter into the peritoneal cavity, twice per week before bedtime. Calcium carbonate or calcium acetate was used as the main phosphate binder. Intact parathyroid hormone level (iPTH), serum ionized calcium (iCa), serum phosphate, and serum total alkaline phosphatase (alk. phos.) levels were measured at baseline and then every 4 weeks. The mean duration of follow-up was 10.5 months +/- 1.9 months. RESULTS: There was a significant drop of iPTH level from the pretreatment level of 100.6 +/- 35.8 pmol/L to a level of 63.8 +/- 48.7 pmol/L at 24 weeks (p = 0.036). The lowest level of iPTH attained was 43.4 +/- 27.0 pmol/L at 48 weeks. Serum total alk. phos. also dropped from 232.4 +/- 83.3 IU/L pretreatment to 147.9 +/- 52.0 IU/L at 24 weeks (p = 0.017). The decrease in alk. phos. level paralleled the decrease in iPTH level. The mean serum iCa level did not show any significant rise throughout the study period. The maximum dose of calcitriol used was 6.6 +/- 1.5 microg/week and the average dose of calcitriol was 5.4 +/- 1.2 microg/week. One patient did not respond satisfactorily and she subsequently had a parathyroidectomy. Two episodes of peritonitis occurred during the study period, giving a peritonitis rate of one episode per 42 patient-months. There was no significant change in the urea clearance tests or the peritoneal equilibration tests before and after the study. CONCLUSION: Intraperitoneal calcitriol is practicable, effective, and safe in the treatment of secondary hyperparathyroidism in CAPD patients.

Highly successful long-term outcome of kidney transplantation in Chinese recipients: an enhancing race effect?

We report on 352 cadaveric kidney transplants and 294 living related transplants performed over a 25-yr period among the Chinese population of Hong Kong. There is a marked preference for transplanting male patients, especially from living donors, and we argue that this represents a cultural phenomenon within the Chinese population. The 10-yr graft survivals for related and cadaveric transplants are 86.2% and 67.4%, respectively. These figures are appreciably higher than corresponding figures in Caucasian populations. We show beneficial effects of using cyclosporin A, minimizing the cold ischemia time and avoiding very young and very old donors. There is a clear benefit of transplanting kidneys with zero or one mismatched HLA antigen against the recipient but no stepwise decrease in outcome as the number of mismatched antigens increases. There is close concordance between the outcome of living related grafts with zero, one, and two mismatched haplotypes against the recipient and no observable benefit of haplotype matching. We show that Chinese renal transplant recipients in other centers also have better long-term graft outcome than Caucasians, both for cadaveric and living related transplants. We draw attention to the existence of a detrimental "race effect" in other studies when Black recipients are compared with Caucasians and consider whether an enhancing race effect exists for Chinese or whether the better outcome reflects different underlying diseases in Chinese.

Adult T cell leukaemia lymphoma in a non-aboriginal Australian woman with no apparent risk factors.

OBJECTIVE: To present a case of adult T cell leukaemia lymphoma (ATLL) in a non-Aboriginal Australian woman with no apparent risk factor. CLINICAL FEATURES: A 43-year-old Australian woman of European descent presented with a febrile illness associated with generalised lymphadenopathy and splenomegaly. INVESTIGATIONS: There was lymphocytosis in the peripheral blood with a T helper cell phenotype. There were also lytic bone lesions with associated hypercalcaemia. HTLV-1 antibody was detected by agglutination assay and confirmed by western blot test. TREATMENT AND OUTCOME: After initial response to CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine, prednisolone), she relapsed and died with central nervous system involvement eight months after the initial diagnosis. CONCLUSION: To our knowledge this is only the third case of ATLL in a non-Aboriginal person in Australia.