A new ecology for scrub typhus associated with a focus of antibiotic resistance in rice farmers in Thailand

Following the documentation of chloramphenicol-resistant and doxycycline-resistant strains of Orientia tsutsugamushi (Hyashi) in northern Thailand, we conducted ecological and epidemiological studies near the houses of patients hospitalized with antibiotic-resistant infections. New associations between chiggers, rodents, and O. tsutsugamushi in active rice agriculture areas, an ecological habitat not described previously, are reported. Rattus rattus (L.) was the most common species (representing 85.8% of the 1,433 rodents processed), followed by Rattus losea (Swinhoe) (9.4%), Bandicota indica (Bechstein) (3.6%), and Rattus argentiventer (Robinson and Kloss) (1.3%). O. tsutsugamushi was isolated from 30% of the R. rattus and R. losea, 29% of the B. indica, and 33% of the R. argentiventer collected. Mean minimum infection rates were 0.03 in Leptotrombidium chiangraiensis Tanskul & Linthicum, a new species of chigger, and 0.002 in Leptotrombidium imphalum (Vercammen-Grandjean & Langston), a chigger species not previously associated with scrub typhus transmission. Efficient vertical and horizontal transmission of O. tsutsugamushi by L. chiangraiensis and L. imphalum was demonstrated. During a 19-mo period from October 1993 to April 1995, the overall prevalence of human IgM and IgG antibody to O. tsutsugamushi was 25.5 and 47.3%, respectively. L. chiangraiensis and L. imphalum are incriminated as vectors of O. tsutsugamushi in a rice field habitat associated with a focus of antibiotic resistance.     

Seroprevalence and epidemiology of Helicobacter pylori infection in patients with cirrhosis

BACKGROUND: Helicobacter pylori infection is the major pathogenic factor for peptic ulcer disease. Its epidemiology is not fully known; few data are available in patients with chronic liver disease. AIMS: To investigate the seroprevalence and factors associated with Helicobacter pylori infection in a series of liver cirrhosis patients. METHODS: Two hundred and twenty consecutive patients were prospectively included in a study aimed to evaluate the effect of dietary intervention on cirrhosis complications and survival. At inclusion, an epidemiological and clinical questionnaire was completed. Sera were obtained and stored at -70 degrees C until analyzed. They were tested for Helicobacter pylori antibodies using a commercial ELISA kit. RESULTS: Eleven out of 220 patients had borderline anti-Helicobacter pylori IgG titers. Of the remaining 209 patients, 105 (50.2%) showed positive titers of Helicobacter pylori IgG. Univariate analysis showed that Helicobacter pylori infection was more frequent in older patients, those born outside Catalonia, and in patients with a low educational level. Past ethanol consumption and current smoking correlated negatively with Helicobacter pylori infection. Multivariate analysis selected age (OR 3.1. 95% CI 1.46-6.45), educational level (OR 2.2. 95% CI 1.18-4.2) and alcohol consumption (OR 0.7. 95% CI 0.45-0.99) as the variables independently related to Helicobacter pylori infection. CONCLUSIONS: Helicobacter pylori infection in cirrhosis has the same epidemiological pattern as in the general population. Suggestions that the etiology or the severity of the liver disease could be related to Helicobacter pylori infection were not confirmed by our study.     

Seroprevalence of B19 parvovirus infection in patients with acute polyarthritis

Over a period of 29 months, from January 1991 to December 1994, all cases of acute polyarthritis seen at the Rheumatology Service in our Institution were studied to determine the seroprevalence of parvovirus B19 (B19) infection. The variables studied included: age and sex of patients, presence of fever and rash, Anti-B19 IgM and IgE serological determinations (ELISA, Mardix Lab.), follow-up time and final diagnosis. The study included 36 patients (22 women and 14 men, mean age 34 +/- 19 years). Thirteen and seven patients had fever and cutaneous rash, respectively. Anti-B19 IgM serology was positive in 4 patients; in 2 of them IgG seroconversion was confirmed. The mean follow-up time was 14 +/- 9 months. Final diagnoses included undifferentiated polyarthritis, rheumatoid arthritis, B19 polyarthritis, systemic lupus erythematosus, and miscellaneous in 19, 7, 4, 2, and 4 patients, respectively. Seroprevalence of B19 infection in acute polyarthritis in our area was 11%, approximately.     

A comparison of three different dihydroartemisinin formulations for the treatment of acute uncomplicated falciparum malaria in Thailand

This study was aimed at assessing the response to electrochemotherapy with cisplatin of cutaneous tumour nodules in patients with malignant melanoma, squamous cell carcinoma and basal cell carcinoma. In 4 patients, 30 tumour nodules of different sizes were treated; five without treatment, one with electric pulses, five with cisplatin injected intratumorally and 19 with electrochemotherapy, i.e. intratumoral administration of cisplatin followed by delivery of electric pulses to the tumour nodule. After 4 weeks, a complete response (CR) in all 19 electrochemotherapy treated nodules was obtained. All electrochemotherapy treated nodules remained in CR (range 7-11 months), regardless of histological type, except for the metastasis of a squamous cell carcinoma that progressed after 9 months. CR was also obtained in two of five tumour nodules treated with cisplatin intratumorally, but the other three nodules progressed within 3-7 months. Exposure of the tumour nodule to electric pulses without cisplatin treatment had no effect on tumour growth. Electrochemotherapy was well tolerated by all patients and a good cosmetic effect was obtained, with only minimal scarring and a slight depigmentation of the skin. Electrochemotherapy with cisplatin has proved to be effective in patients with cutaneous tumour nodules. Furthermore, electrochemotherapy is easy to perform and can be carried out on an out-patient basis.     

Seroprevalence study of HTLV-1 and HIV infection in blood donors and patients with lymphoid malignancies in Lagos, Nigeria

OBJECTIVE: To document the seroprevalence of HTLV-1 and HIV in blood donors and in patients with lymphoma and leukaemia in Lagos metropolis. DESIGN: Cross sectional. SETTING: The Lagos University Teaching Hospital (LUTH) and General Hospital, Lagos (GH). SUBJECTS: 406 apparently healthy voluntary blood donors from the LUTH and GH and 30 patients [20 patients with histological diagnosis of Non-Hodgkin's Lymphoma (NHL) and 10 patients with diagnosis of Chronic Lymphocytic Leukaemia (CLL)] were recruited at LUTH. MAIN OUTCOME MEASURES: HTLV-1 and HIV-1 seroprevalence. RESULTS: Out of 406 donors, three (0.7%) were positive for HTLV-1 and 20 (4.9%) were positive for HIV-1. None of the 30 patients with NHL or CLL were positive for HTLV-1. Five of NHL patients were positive for HIV-1. CONCLUSION: HTLV-1 seroprevalence is low among Lagos donors. Routine screening of donors for this virus will not be cost effective. NHL is one of the AIDS related malignancies which has been documented in this study.     

Rifabutin versus placebo in combination with three drugs in the treatment of nontuberculous mycobacterial infection in patients with AIDS

OBJECTIVE: Most endoscopic perforations of the colon occur in the rectosigmoid area and are thought to be secondary to direct injury from the endoscopic instrument. The aim of this study was to describe the mechanisms of injury and clinical outcome of endoscopic perforation involving the cecum. METHODS: Retrospective review of 6684 consecutive colonoscopic procedures performed at a university hospital over a 7-yr period. RESULTS: Colonoscopy was complicated by perforation in 0.22%. Five of the 15 perforations occurred in the cecum. The mean age of these five patients was 79.6 +/- 17.7 yr (mean +/- SD). Indications for the procedure were bleeding (n = 4) and suspected obstructing cecal mass (n = 1). Abnormal endoscopic findings included diverticulosis, vascular malformations, cecal ulcer/inflammation, mass, and polyps. Perforation was directly attributable to an ancillary procedure (three routine biopsies, one electrocautery) in the cecal area in four patients, and cecal pathology (inflammation, ulceration) was a contributing risk factor in three patients. Mortality was 80%. In contrast, a noncecal perforation usually occurred at the sigmoid region and was associated with technical difficulties, e.g., inability to traverse a stricture or reach the cecum. CONCLUSIONS: Routine forceps biopsy (without electrocautery) is an under-recognized cause of cecal perforation. Ancillary endoscopic interventions in the cecal region should be minimized in elderly patients with evidence of cecal inflammation. Pneumatic injury may be an additional risk factor for cecal perforation in patients with a colonic stricture or a tortuous colon.     

Pharmacokinetics of proguanil in malaria patients treated with proguanil plus atovaquone

Clinical studies have shown atovaquone (ATQ), a new blood schizontocidal drug, in combination with proguanil (PROG) to be very effective in the treatment of acute multidrug-resistant falciparum malaria. The multiple dose pharmacokinetics of PROG were determined in Thai patients with acute falciparum malaria given PROG alone (200 mg PROG twice a day for 3 days, n = 4) and concurrently PROG and ATQ (200 mg PROG and 500 mg ATQ twice a day for 3 days, n = 12). There were no statistical differences (p > 0.05) in the area under the plasma drug concentration-time curve (AUC), apparent oral clearance (CL/F) and elimination half-life (t1/2) of PROG between patients given PROG alone and PROG/ ATQ. The median (range) kinetic values of PROG in patients given PROG alone and PROG/ATQ were respectively: CL/F = 1.25 l/h/kg (0.99-1.45) and 0.95 (0.73-1.32) l/h/kg, and t1/2 = 14.2 hours (9.3-16.8) and 13.6 hours (9.1-17.6). The CL/F and t1/2 of PROG in the Thai patients treated with the 2 treatment regimens were also comparable to values reported in healthy Thai volunteers given a standard prophylactic dose (200 mg PROG). The results of this preliminary study suggest that ATQ is unlikely to affect the pharmacokinetics of PROG to a clinically important extent at an ATQ dosage of 500 mg twice a day for 3 days in malaria infected patients.     

Seroprevalence of hepatitis B and C viral markers in patients with primary hepatocellular carcinoma in Singapore

This paper reviews studies on the basic principles of biostimulation of wound healing by various low-energy lasers. It looks at the mechanism of action of biostimulation as well as the laser's effect on cell proliferation, collagen synthesis, and would healing.     

Prevalence of hypertension in patients with type II diabetes in referral versus primary care clinics

We report our clinical experience in managing a 59-year-old Italian male with Churg-Strauss syndrome (CSS) whose first clinical manifestation was a persistent dysphonia; the patient worked as a mechanic. Video-laryngostroboscopic examination revealed paresis of the right vocal fold with a reduction in adduction together with incomplete glottal closure. Spectrographic and spirometric tests both showed abnormal changes. Laryngeal electromyography revealed neurogenic damage of the right thyroarytenoid and crycoarytenoid muscles. Due to the appearance of typical signs of systemic involvement of CSS as a necrotizing vasculitis, the patient was admitted to the Rheumatology Unit of the University of Pisa. Histologic analysis of a skin lesion on the patient's foot confirmed the diagnosis. Treatment with 6-methylprednisolone quickly brought remission from systemic and laryngeal symptoms, as well as improvement in the results of video-laryngostroboscopic, spectrographic and laryngeal myographic tests.     

Efficacy of sulfadoxine-pyrimethamine for prevention of placental malaria in an area of Kenya with a high prevalence of malaria and human immunodeficiency virus infection

Our current knowledge of mammalian forebrain development is meagre. The comparatively few relevant anatomical landmarks are, however, being supplemented by gene expression studies which are able to identify subsets of anatomical structures. We previously described cloning, subchromosomal localization and preliminary structural characterization of the human WNT8B gene, the first mammalian Wnt8b gene to be reported. Wnt genes encode intercellular signalling molecules which play a variety of critical roles in early development, including, in several cases, a presumed role in brain development. In the current report we present the full-length cDNA sequence and genomic organization of the human Wnt8b gene and report studies of expression of the Wnt8b gene in human and mouse embryos. The human and mouse expression patterns appeared identical and were restricted to the developing brain, with the great majority of expression being found in the developing forebrain. In the latter case expression was confined to the germinative neuroepithelium of three sharply delimited regions: the dorsomedial wall of the telencephalic ventricles (which includes the developing hippocampus), a discrete region of the dorsal thalamus and the mammillary and retromammillary regions of the posterior hypothalamus. Expression in the developing hippocampus may suggest a role for WNT8B in patterning of this region and subchromosomal localization of the human gene to 10q24 may suggest it as a candidate gene for partial epilepsy in families where the disease has been linked to markers in this region.     

Evaluation of atovaquone in the treatment of patients with uncomplicated Plasmodium falciparum malaria

The activity of atovaquone in patients with oligosymptomatic Plasmodium falciparum malaria was assessed in an open, non-comparative clinical study. The patients showed a good clinical response, but there was a high rate of recrudescence. The activity of atovaquone in combination with another antimalarial agent should be investigated.     

Seroprevalence of HBV, HCV and HDV hepatitis markers in 500 patients infected with the human immunodeficiency virus

The serological status for both hepatitis B, C and D viruses was analyzed for 500 HIV seropositive patients and for 1037 of a control group. The prevalence was 31.4% for anti HCV, 13.8% for HBs Ag and 69.0% for one or more HBV markers in HIV positive patients and respectively 2.5%, 2.7% and 13.1% in control group. The markers for hepatitis D were founded among 21% of the HBs Ag carriers (patients and control group), correlated with drug i.v. use. The prevalence of anti-HCV was 71.6% in subjects who had blood-borne HIV infection and 1.5% in those with sexually acquired infection. The prevalence in control group was 10.2% and 1.7% respectively according to the same risk factors. The prevalence of HBs Ag was higher among HIV positive patients with sexual risk (17.5%) than with blood exposition (9.9%) and a variation in the same direction is observed in control group (3% v.s. 1%). The relation between markers for hepatitis B and hepatitis C was negative.     

Rates of flu-like infection in patients with affective illness

Studies of immunologic profiles of depressed patients are suggestive of chronic viral infection and several investigators have found specific viral protein in some depressed patients. Moreover, several psychotropic drugs have anti-viral activity and can inhibit viral replication. In this preliminary report, we retrospectively examined the rate of reported flu-like episodes before and during psychotropic drug treatment in 236 affectively ill patients: 177 receiving lithium prophylaxis and 59 receiving chronic antidepressant medication. We observed a small but significant reduction in the mean rate of reported flu-like illness during lithium therapy (P < 0.001), with a greater reduction in men vs. women (P < 0.05). We also found a modest reduction in reported flu-like illness during chronic treatment with antidepressants (P = 0.08). Although these observations are preliminary in nature, they complement earlier reports that some psychotropic drugs may have anti-viral activity.     

Results of renal transplantation in patients with Schistosoma infection

PURPOSE: We evaluated the results of renal transplantation in patients infected with Schistosoma haematobium, as well as the risks of urological complications and post-transplant reinfection. MATERIALS AND METHODS: The outcome of 20 kidney transplants was retrospectively studied. Based on our experience and review of the literature, our clinical practice to prevent urological complications consisted of antischistosomal chemotherapy given at the pre-transplant evaluation, with endovesical ureteroneocystostomy preferred in case of bladder calcifications. A Foley catheter was maintained for 10 days. A transurethral bladder neck incision was performed before removal of the Foley catheter when bladder neck sclerosis was present. RESULTS: The 1 and 2-year patient survival rate was 93%, and 1 and 2-year graft survival rates were 88 and 81%, respectively, which were not different from those of a cohort of 167 patients without schistosomal infection. Surgical complications included 2 postoperative hemorrhages, 2 urinary leaks and 1 nonschistosomal related ureteral stricture. Post-transplant schistosomal infection never occurred when antischistosomal chemotherapy was given at the pre-transplant evaluation. CONCLUSIONS: Patients with schistosomal infection are suitable recipients for kidney transplantation, although they are at risk for urological complications. Unlike other infectious diseases, such as tuberculosis, the risk of recurrence due to reactivation of chronically hosted pathogens seems to be low or absent in patients who received antischistosomal chemotherapy at the pre-transplant evaluation. Long-term urological followup is recommended, including urethrocystoscopy, because of the theoretically increased risk for bladder malignancy.     

Oxidative stress and antioxidative status of plasma and erythrocytes in patients with vivax malaria

OBJECTIVES: To investigate the oxidative stress and antioxidative status of plasma and erythrocytes in patients with vivax malaria and healthy persons. DESIGN AND METHODS: Activities of antioxidative enzymes, rates of pathways of hexose monophosphate shunt and purine salvage, levels of lipid peroxidation, reduced glutathione, methemoglobin and sulfhemoglobin of erythrocytes were determined. Lipid peroxidation and levels of antioxidant substances were measured. RESULTS: Antioxidants levels and antioxidative enzymes activities were lower and lipid peroxidation, purine salvage rate were higher in patients group than controls. Erythrocyte glucose-6 phosphate dehydrogenase (G-6-PD) activity was not different from that of healthy subjects. CONCLUSIONS: Oxidative mechanisms were observed to be dominant compared with antioxidative mechanisms in patients with vivax malaria. Therefore, oxidative stress may be produced and maintained by the host defense mechanisms against malarial infection.