Long-term kidney function recovery and mortality after COVID-19-associated acute kidney injury: An international multi-centre observational cohort study

Background

While acute kidney injury (AKI) is a common complication in COVID-19, data on post-AKI kidney function recovery and the clinical factors associated with poor kidney function recovery is lacking.

Methods

A retrospective multi-centre observational cohort study comprising 12,891 hospitalized patients aged 18 years or older with a diagnosis of SARS-CoV-2 infection confirmed by polymerase chain reaction from 1 January 2020 to 10 September 2020, and with at least one serum creatinine value 1-365 days prior to admission. Mortality and serum creatinine values were obtained up to 10 September 2021.

Findings

Advanced age (HR 2.77, 95%CI 2.53-3.04, p < 0.0001), severe COVID-19 (HR 2.91, 95%CI 2.03-4.17, p < 0.0001), severe AKI (KDIGO stage 3: HR 4.22, 95%CI 3.55-5.00, p < 0.0001), and ischemic heart disease (HR 1.26, 95%CI 1.14-1.39, p < 0.0001) were associated with worse mortality outcomes. AKI severity (KDIGO stage 3: HR 0.41, 95%CI 0.37-0.46, p < 0.0001) was associated with worse kidney function recovery, whereas remdesivir use (HR 1.34, 95%CI 1.17-1.54, p < 0.0001) was associated with better kidney function recovery. In a subset of patients without chronic kidney disease, advanced age (HR 1.38, 95%CI 1.20-1.58, p < 0.0001), male sex (HR 1.67, 95%CI 1.45-1.93, p < 0.0001), severe AKI (KDIGO stage 3: HR 11.68, 95%CI 9.80-13.91, p < 0.0001), and hypertension (HR 1.22, 95%CI 1.10-1.36, p = 0.0002) were associated with post-AKI kidney function impairment. Furthermore, patients with COVID-19-associated AKI had significant and persistent elevations of baseline serum creatinine 125% or more at 180 days (RR 1.49, 95%CI 1.32-1.67) and 365 days (RR 1.54, 95%CI 1.21-1.96) compared to COVID-19 patients with no AKI.

Interpretation

COVID-19-associated AKI was associated with higher mortality, and severe COVID-19-associated AKI was associated with worse long-term post-AKI kidney function recovery.

Funding

Authors are supported by various funders, with full details stated in the acknowledgement section.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

MRI in acute muscle tears in athletes: can quantitative T2 and DTI predict return to play better than visual assessment?

OBJECTIVES

To assess the ability of quantitative T2, diffusion tensor imaging (DTI) and radiologist's scores to detect muscle changes following acute muscle tear in soccer and rugby players. To assess the ability of these parameters to predict return to play times.

METHODS

In this prospective, longitudinal study, 13 male athletes (age 19 to 34 years; mean 25 years) underwent MRI within 1 week of suffering acute muscle tear. Imaging included measurements of T2 and DTI parameters. Images were also assessed using modified Peetrons and British athletics muscle injury classification (BAMIC) scores. Participants returned for a second scan within 1 week of being determined fit to return to play. MRI measurements were compared between visits. Pearson's correlation between visit 1 measurements and return to play times was assessed.

RESULTS

There were significant differences between visits in BAMIC scores (Z = - 2.088; p = 0.037), modified Peetrons (Z = - 2.530; p = 0.011) and quantitative MRI measurements; T2, 13.12 ms (95% CI, 4.82 ms, 21.42 ms; p = 0.01); mean diffusivity (0.22 (0.04, 0.39); p = 0.02) and fractional anisotropy (0.07 (0.01, 0.14); p = 0.03). BAMIC scores showed a significant correlation with return to play time (Rs = 0.64; p = 0.02), but modified Peetrons scores and quantitative parameters did not.

CONCLUSIONS

T2 and DTI measurements in muscle can detect changes due to healing following muscle tear. Although BAMIC scores correlated well with return to play times, in this small study, quantitative MRI values did not, suggesting that T2 and DTI measurements are inferior predictors of return to play time compared with visual scoring.

KEY POINTS

• Muscle changes following acute muscle tear can be measured using T2 and diffusion measurements on MRI. • Measurements of T2 and diffusion using MRI are not as good as a radiologist's visual report at predicting return to play time after acute muscle tear.

Quantitative MRI in myositis patients: comparison with healthy volunteers and radiological visual assessment

AIM

To assess whether magnetic resonance imaging (MRI)-based measurements of T2, fat fraction, diffusion tensor imaging, and muscle volume can detect differences between the muscles of myositis patients and healthy controls, and to identify how they compare with semi-quantitative MRI diagnosis.

MATERIALS AND METHODS

Sixteen myositis patients and 16 age- and gender-matched healthy controls underwent MRI of their thigh. Quantitative MRI measurements and radiologists' semi-quantitative scores were assessed. Strength was assessed using an isokinetic dynamometer.

RESULTS

Fat fraction and T2 values were higher in myositis patients whereas muscle volume was lower compared to healthy controls. There was no difference in diffusion. Muscle strength was lower in myositis patients compared to healthy controls. In a subgroup of eight patients, scored as unaffected by radiologists, T2 values were still significantly higher in myositis patients.

CONCLUSIONS

Quantitative MRI measurements can detect differences between myositis patients and healthy controls. Changes in the muscles of myositis patients, undetected by visual, semi-quantitative scoring, can be detected using quantitative T2 measurements. This suggests that MRI T2 values may be useful for the management of myositis patients.

Epidemiology and clinical characteristics of invasive mould infections: A multicenter, retrospective analysis in five Asian countries

Formal, large-scale, multicenter studies of invasive mould infection (IMI) in Asia are rare. This 1-year, retrospective study was designed to assess the incidence and clinical determinants of IMI in centers in five countries (Thailand, Taiwan, Singapore, China, India). Patients treated in a single year (2012) were identified through discharge diagnoses, microbiology, and histopathology logs, and entered based on published definitions of IMI. A total of 155 cases were included (median age 54 years; 47.7% male). Of these, 47.7% had proven disease; the remainder had probable IMI. The most frequent host factors were prolonged steroid use (39.4%) and recent neutropenia (38.7%). Common underlying conditions included diabetes mellitus (DM; 30.9%), acute myeloid leukemia (19.4%), and rheumatologic conditions (11.6%). DM was more common in patients with no recent history of neutropenia or prolonged steroid use (P = .006). The lung was the most frequently involved site (78.7%), demonstrating a range of features on computed tomography (CT). Aspergillus was the most common mould cultured (71.6%), primarily A. fumigatus and A. flavus, although proportions varied in different centers. The most often used antifungal for empiric therapy was conventional amphotericin. Ninety-day mortality was 32.9%. This is the first multicenter Asian study of IMI not limited to specific patient groups or diagnostic methods. It suggests that DM and rheumatologic conditions be considered as risk factors for IMI and demonstrates that IMI should not be ruled out in patients whose chest features on CT do not fit the conventional criteria.

Donor-Derived Candida dubliniensis Resulting in Perigraft Abscesses in a Liver Transplant Recipient Proven by Whole Genome Sequencing: A Case Report

BACKGROUND

The transmission of fungi via transplant, although well-known, has not often been molecularly proven. We describe a case of donor-derived candidiasis verified by whole genome sequencing.

CASE DESCRIPTION

The multiorgan donor was a 42-year-old woman with subdural hemorrhage. Procurement of the thoracic organs was performed followed by the abdominal organs. Tissue from the left bronchus grew Candida dubliniensis. The liver recipient was a 63-year-old woman with cryptogenic liver cirrhosis. She was noted to have worsening leukocytosis on postoperative day (POD) 9. Computed tomography of the abdomen and pelvis showed multiple rim-enhancing collections around the graft. Percutaneous drainage was performed. Fluid cultures grew C dubliniensis. C dubliniensis isolated from the donor's left bronchus and the liver recipient's abscesses were verified to be related by whole genome sequencing. We postulate that C dubliniensis colonizing the donor's transected trachea could have contaminated the inferior vena cava when the former was left open after explant of the donor's lungs. A portion of the donor's contaminated inferior vena cava was transplanted along with the liver graft, resulting in the infected collections in the recipient.

CONCLUSIONS

Our case report highlights the importance of maintaining a sterile field during organ procurement, especially in a multiorgan donor whose organs are explanted in succession.

Case Report: Spontaneous Hemorrhage of a Rare Renal Tumor in the Native Kidney of a Renal Transplant Recipient

Renal cancers are some of the most common solid organ malignancies found during follow-up of patients who have undergone renal transplantation (RT). In this case report, we describe a life-threatening spontaneous hemorrhage of a rare subtype of renal cell carcinoma in the native kidney of a 27-year-old man, 4 years after RT. After fluid resuscitation and stabilization, the patient underwent emergent open radical nephrectomy with the final histopathology reporting T1bN0Mx mucinous tubular and spindle cell (MTSC) carcinoma. This case report highlights the need to consider an underlying malignancy in patients who presents with spontaneous hemorrhage of native kidneys after RT.

Recurrent trichosporonosis with central nervous system involvement in an allogeneic hematopoietic stem cell transplant recipient

Trichosporon is an ubiquitous yeast that has emerged as an opportunistic pathogen in the immunocompromised host. We describe a case of invasive trichosporonosis in an allogeneic hematopoietic stem cell transplant (allo-HSCT) recipient while on caspofungin antifungal prophylaxis. She developed disseminated trichosporonosis in the pre-engraftment period and was successfully treated with voriconazole. She later developed 2 further episodes of invasive trichosporonosis involving the central nervous system. This case highlights the challenges of managing trichosporonosis in allo-HSCT recipients and suggests the need for lifelong therapy in some patients.

Incidence and species distribution of candidaemia in Asia: a laboratory-based surveillance study

The epidemiology of candidaemia varies between hospitals and geographic regions. Although there are many studies from Asia, a large-scale cross-sectional study across Asia has not been performed. We conducted a 12-month, laboratory-based surveillance of candidaemia at 25 hospitals from China, Hong Kong, India, Singapore, Taiwan and Thailand. The incidence and species distribution of candidaemia were determined. There were 1601 episodes of candidaemia among 1.2 million discharges. The overall incidence was 1.22 episodes per 1000 discharges and varied among the hospitals (range 0.16-4.53 per 1000 discharges) and countries (range 0.25-2.93 per 1000 discharges). The number of Candida blood isolates and the total number of fungal isolates were highly correlated among the six countries (R² = 0.87) and 25 hospitals (R² = 0.77). There was a moderate correlation between incidence of candidaemia and the intensive care unit (ICU)/total bed ratio (R² = 0.47), although ICUs contributed to only 23% of candidaemia cases. Of 1910 blood isolates evaluated, Candida albicans was most frequently isolated (41.3%), followed by Candida tropicalis (25.4%), Candida glabrata (13.9%) and Candida parapsilosis (12.1%). The proportion of C. tropicalis among blood isolates was higher in haemato-oncology wards than others wards (33.7% versus 24.5%, p 0.0058) and was more likely to be isolated from tropical countries than other Asian countries (46.2% versus 18.9%, p 0.04). In conclusion, the ICU settings contribute, at least in part, to the incidence variation among hospitals. The species distribution is different from Western countries. Both geographic and healthcare factors contribute to the variation of species distribution.

Role of vascular channels as a novel mechanism for subchondral bone damage at cruciate ligament entheses in osteoarthritis and inflammatory arthritis

OBJECTIVES

The purpose of this work was to test whether normal peri-entheseal vascular anatomy at anterior and posterior cruciate ligaments (ACL and PCL) was associated with distribution of peri-entheseal bone erosion/bone marrow lesions (BMLs) in inflammatory arthritis (IA) and osteoarthritis (OA).

METHODS

Normal microanatomy was defined histologically in mice and by 3 T MRI and histology in 21 cadaveric knees. MRI of 89 patients from the Osteoarthritis Initiative and 27 patients with IA was evaluated for BMLs at ACL and PCL entheses. Antigen-induced arthritis (AIA) in mice was evaluated to ascertain whether putative peri-entheseal vascular regions influenced osteitis and bone erosion.

RESULTS

Vascular channels penetrating cortical bone were identified in knees of non-arthritic mice adjacent to the cruciate ligaments. On MRI of normal cadavers, vascular channels adjacent to the ACL (64% of cases) and PCL (71%) entheses were observed. Histology of 10 macroscopically normal cadaveric specimens confirmed the location of vascular channels and associated subclinical changes including subchondral bone damage (80% of cases) and micro-cyst formation (50%). In the AIA model, vascular channels clearly provided a site for inflammatory tissue entry and osteoclast activation. MRI showed BMLs in the same topographic locations in both patients with early OA (41% ACL, 59% PCL) and IA (44%, 33%).

CONCLUSION

The findings show that normal ACL and PCL entheses have immediately adjacent vascular channels which are common sites of subtle bone marrow pathology in non-arthritic joints. These channels appear to be key determinants in bone damage in inflammatory and degenerative arthritis.

Chemotherapy extravasation at hospital pulau pinang, malaysia

PURPOSE

Extravasation with intravenous chemotherapy is a common complication of chemotherapy which carries the risk of devastating complications. This study aims to determine the rate of extravasation with intravenous chemotherapy in a major hospital where chemotherapy is delivered in various departments other than the oncology department.

PATIENTS AND METHODS

All patients who underwent intravenous chemotherapy in the oncology department and surgical wards in Penang General hospital from 1st February 2008 till 31st June 2008 were recruited retrospectively for this study to look at the rate of extravasation.

RESULTS

A total of 602 patients underwent intravenous chemotherapy during this period. Fifty patients received chemotherapy in the general surgical ward while another 552 patients received chemotherapy in the oncology department. There were 5 cases of extravasation giving an overall extravasation rate of 0.8% (5/602). however, 4 of these cases occurred in the general surgical ward giving it a rate of 8% (4/50).

CONCLUSION

The rate of extravasation in our hospital was 0.8%. however, this rate can be significantly increased if it is not done under a specialized unit delivering intravenous chemotherapy on a regular basis. Preventive steps including a standard chemotherapy delivery protocol, staff and patient education must be put in place in all units delivering intravenous chemotherapy.

Isolation of the first three cases of Clostridium difficile polymerase chain reaction ribotype 027 in Singapore

INTRODUCTION

The incidence of Clostridium (C.) difficile infection (CDI) was on the rise from 2001 to 2006 in Singapore. Recent unpublished data suggests that its incidence had remained stable or decreased in most local public hospitals between 2006 and 2010. It is, however, not known if the polymerase chain reaction (PCR) ribotype 027 strains have been circulating, although reports suggest that this strain is emerging in Asia, with the first cases reported from Japan in 2007, as well as in Hong Kong and Australia in 2009. We initiated a culture-based surveillance to detect this epidemic strain in Singapore.

METHODS

From September 2008 to December 2009, all non-duplicate toxin-positive stool samples from the three largest public hospitals in Singapore were collected for culture and further analysis.

RESULTS

Out of the 366 samples collected, 272 viable isolates were cultured. Of these, 240 tested toxin-positive and ten tested positive for the binary toxin gene; 35 different PCR ribotypes were found. Three isolates that tested positive for binary toxin contained the same PCR ribotyping pattern as the C. difficile 027 control strain. All three had the 18-bp deletion and single nucleotide tcdC deletion at position 117. Susceptibility testing was performed, demonstrating susceptibility to erythromycin and moxifloxacin.

CONCLUSION

We report the first three isolates of C. difficile 027 from Singapore. However, their susceptibility patterns are more consistent with the historical 027 strains. Rising CDI incidence may not be associated with the emergence of the epidemic 027 strain at this time.

Abstract P5-11-18: Investigating Early Features of Aromatase Inhibitor-Induced Arthralgia

Background: Aromatase inhibitors (AI) are well known to be associated with troublesome musculoskeletal side effects but the underlying mechanisms are poorly understood and methods of objective assessment poorly defined. We have performed a prospective detailed evaluation of grip strength (primary endpoint), symptoms, imaging and biomarkers in patients receiving either an AI, tamoxifen or no endocrine therapy. Methods: 77 patients with early breast cancer from two specialist Breast Units were recruited prior to starting one of 4 treatment arms: upfront AI (A), switch from tamoxifen to AI (B), tamoxifen (C) and no treatment (D). Arthralgia was defined as worsening of joint pain score at 3 months and a positive Tinel's or Phalen's test was taken as evidence of carpal tunnel syndrome. Grip strength was measured (average of three readings from each hand) using a Jamar Dynamometer at baseline, 1, 2, 3, 6 and 12 months. In addition, biochemical (endocrine and collagen markers), rheumatological (inflammatory and cytokine markers) and radiological assessments of the hands (diagnostic ultrasound, bone density using DXA and plain radiograph) were performed at protocol-specified intervals. A subset of patients also underwent hand MRI at baseline, 3 and 12 months. Detailed rheumatological examination and questionnaire (DAS-28, SF-36, HAQ-DI and BPI-SF) assessment were performed at each visit. Grip strength was analysed using analysis of covariance with age, prior chemotherapy and baseline grip as covariates. The Kruskal-Wallis test was used for questionnaire data. The 3 month data on grip strength, questionnaire, clinical assessment and hand ultrasound are presented here. Results: 47 patients received an AI (34 upfront, 13 switch), 22 tamoxifen and 8 no endocrine treatment (controls). Median age (yearrs) for each group was: 62.1 (A), 51.0 (B), 65.2 (C) and 61.2 (D). The incidence of arthralgia at 3 months was 38% (A), 17% (B), 38% (C) and 14% (D). Mean baseline grip strength was similar in each arm: 22.5kg (A), 23.1kg (B), 20.2kg (C) and 23.2kg (D) (p=0.342 ANOVA). At 3 months, the mean percentage change in grip strength was +0.2% (A), +2.2% (B), +4.5% (C),+1.2% (D) (p=ns ANCOVA). In those on AI, the development of arthralgia was not shown to be associated with change in grip strength (p=0.82). Morning stiffness was also no different at 3 months. Clinical signs of carpal tunnel syndrome were evident in 10/45 (22%) of patients receiving AI therapy compared to 4/28 (14%) on tamoxifen/control. There were 4 cases of trigger thumb or finger, all in patients receiving AI treatment. Changes in HAQ-DI and pain (VAS) at 3 months were no different between groups (p=0.27, p=0.1 respectively). Ultrasound assessment of the flexor tendons at 3 month identified an increase in median score for tendon sheath fluid in those in the AI groups (3 (AI) v 1 (No AI) p=0.07, Mann-Whitney U test). There was no significant change in average median nerve cross-sectional area at 3 month.

Conclusion: This study suggests that patient reported arthalgia does not correlate with early changes in and mean grip strength. However, there may be early signs of carpal tunnel syndrome, trigger finger and fluid in the flexor tendon sheaths detectable by ultrasound.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-11-18.

A Short Measure of Eriksonian Ego Identity

Developed a new measure of Erikson's (1950, 1959) concept of ego identity which would meet the following criteria: (a) that it be short, with an acceptable level of reliability; (b) that it be objective and easily scored; and (c) that it be free of response set contamination. A 12-item scale (Ego Identity Scale) with a forced choice format was constructed. Two further studies were conducted to test the validity of the scale. These studies showed that the Ego Identity Scale correlated as predicted with measures Of locus of control, intimacy, dogmatism, Tomkins' Left, occupational commitment, and political commitment. It also correlated in the predicted direction with measures of interpersonal trust and moral commitment though these correlations did not reach statistical significance.

Surveillance of antibiotic resistance in Neisseria gonorrhoeae in the WHO Western Pacific and South East Asian regions, 2007-2008

Long-term surveillance of antimicrobial resistance in Neisseria gonorrhoeae has been conducted in the World Health Organization (WHO) Western Pacific Region (WPR) to optimise antibiotic treatment of gonococcal disease since 1992. In 2007 and 2008, this Gonococcal Antimicrobial Surveillance Programme (GASP) was enhanced by the inclusion of data from the South East Asian Region (SEAR) and recruitment of additional centres within the WPR. Approximately 17,450 N. gonorrhoeae were examined for their susceptibility to one or more antibiotics used for the treatment of gonorrhoea by external quality controlled methods in 24 reporting centres in 20 countries and/or jurisdictions. A high proportion of penicillin and/or quinolone resistance was again detected amongst isolates tested in North Asia and the WHO SEAR, but much lower rates of penicillin resistance and little quinolone resistance was present in most of the Pacific Island countries. The proportion of gonococci reported as 'resistant', 'less susceptible' or 'non-susceptible' gonococci to the third-generation cephalosporin antibiotic ceftriaxone lay in a wide range, but no major changes were evident in cephalosporin minimal inhibitory concentration (MIC) patterns in 2007-2008. Altered cephalosporin susceptibility was associated with treatment failures following therapy with oral third-generation cephalosporins. There is a need for revision and clarification of some of the in vitro criteria that are currently used to categorise the clinical importance of gonococci with different ceftriaxone and oral cephalosporin MIC levels. The number of instances of spectinomycin resistance remained low. A high proportion of strains tested continued to exhibit a form of plasmid mediated high level resistance to tetracyclines. The continuing emergence and spread of antibiotic resistant gonococci in and from the WHO WPR and SEAR supports the need for gonococcal antimicrobial resistance surveillance programs such as GASP to be maintained and potentially expanded.

Imaging of seronegative spondyloarthritis

Magnetic resonance imaging (MRI) and ultrasonography (US) are useful adjuncts in the diagnosis of seronegative spondyloarthritides (SpA); a group of diseases that present early at a stage when radiographic assessment is invariably normal. This chapter will review how MRI and US can be used in the evaluation of early SpA. The diffuse osteitis/enthesitis on MRI may serve as a diagnostic hallmark for SpA spinal disease, but needs confirmatory studies for comparison with other spinal pathologies. MRI is the modality of choice for monitoring axial disease in anti-tumour necrosis factor (TNF) therapy responses in the research environment, but it is not yet certain whether this will be relevant in clinical practice. Anti-TNF therapy may be associated with regression of MRI-determined osteitis, but retardation of associated bony fusion is debatable. MRI and US are still undergoing evaluation for the diagnosis of enthesitis of the appendicular skeleton; US, in particular, shows promise at these sites.

Heberden's nodes and what Heberden could not see: the pivotal role of ligaments in the pathogenesis of early nodal osteoarthritis and beyond

Despite its relatively high prevalence, polyarticular nature, limited treatment options and recognized genetic contribution, the study of generalized OA (GOA) has lagged behind that of isolated knee OA. Whilst the pathogenesis of OA has been viewed in relation to either articular cartilage or bone disease, this article offers a viewpoint on why GOA may, in fact, be primarily a disorder of ligaments, and to a lesser extent tendon and joint capsule dysfunction. A relatively fast presentation of GOA, typically in the perimenopausal period, and its recognition on clinical grounds alone makes this type of OA potentially useful for pathogenic studies in OA, in general. The recent high-resolution MRI studies, microanatomical studies and animal models, in addition to established clinical and radiographic data that support this ligament-centric perspective of disease, are reviewed. The earliest structural abnormalities in GOA may be evident in ligaments and the ligament-associated 'enthesis organ', where degenerative changes are evident. Ligaments also influence the expression of joint damage including Heberden's node and joint erosion formation. Joint inflammation in a 'periarthritis' pattern is well recognized in GOA, and histological studies have shown that the ligament and capsule could represent the epicentre of such inflammatory changes. A perspective is also offered on how ligaments could play a pivotal role in OA in general; for example, the loss of joint space in knee OA due to meniscal extrusion could ultimately be related to derangement of the medial collateral ligament to which the meniscus is anchored.

MR imaging of erosions in interphalangeal joint osteoarthritis: is all osteoarthritis erosive?

OBJECTIVE

Erosive osteoarthritis is usually considered as an inflammatory subset of osteoarthritis (OA). However, an inflammatory component is now recognised in all subsets of OA, so this subgroup of erosive or inflammatory OA is more difficult to conceptualise. The aim of this study was to compare routine CR and MRI to investigate erosion numbers and morphology to determine whether hand OA in general is a more erosive disease than previously recognised.

DESIGN AND METHODS

Fifteen patients with clinical (OA) of the small joints of the hand underwent MRI of one of the affected proximal interphalangeal (PIP) or distal interphalangeal (DIP) joints. Conventional radiographs (CR) of the hand were also obtained. The MR images were reviewed by two observers for the presence of central and marginal erosions. The site and morphology of any erosions was recorded. CR images of the same hand joint were scored independently for central and marginal erosions by the same observers.

RESULTS

There was 100% agreement between the observers for scoring erosions on CR. Agreement for the MRI scores was also excellent (kappa = 0.84). MRI detected 37 erosions, of which only 9 were seen on CR. The increase in sensitivity using MRI was much greater for marginal erosions (1 detected on CR, 19 on MRI) than for central erosions (8 on CR, 18 on MRI). Using MRI 80% of joints examined showed 1 or more erosions compared with 40% using CR. If only marginal erosions were considered 80% of joints were still considered erosive by MRI criteria, but only 1 showed evidence of erosion on CR. Morphologically central erosions appeared to represent areas of subchondral collapse and pressure atrophy. In contrast, marginal erosions resembled those seen in inflammatory arthritides.

CONCLUSION

Erosions, and particularly marginal erosions typical of those seen in inflammatory arthritis, are a more common feature of small joint OA than conventional radiographs have previously indicated.

The relationship between the extensor tendon enthesis and the nail in distal interphalangeal joint disease in psoriatic arthritis--a high-resolution MRI and histological study

OBJECTIVES

Diffuse swelling of the distal interphalangeal (DIP) joint beyond the joint margin is a common feature of arthritis in psoriatic arthritis (PsA). The purpose of this study was to explore the microanatomical basis for the inflammation and nail disease in PsA using a combined high-resolution magnetic resonance imaging (MRI) and histological studies.

METHODS

High-resolution MRIs of the DIP joint were obtained in 30 subjects [10 PsA, 10 osteoarthritis (OA) and 10 normal volunteers]. The relationship between the DIP joint capsule and associated tendon enthesis and the nail bed and root were evaluated. Histological studies to define the relationship between the normal cadaveric DIP joint capsule and the nail root were performed on the middle and ring fingers of 10 dissecting room cadavers.

RESULTS

On MRI, the dorsal capsular enthesis was the epicentre of an inflammatory reaction. This extended to involve the soft tissues adjacent to the nail in 8 of 10 cases in PsA, but only 4 of 10 cases in OA where the inflammation is less intense and in none of the normal fingers. The DIP joint capsule was intimately linked with the nail complex on histology, with the dorsal, volar and lateral aspects of the nail bed being ensheathed in fibres extending from the entheses.

CONCLUSION

The study suggests that the extended nature of the enthesis organ associated with the DIP joint may explain the diffuse nature of the inflammatory response around the nail in PsA. Therefore the nail is as much an integral part of the enthesis organ as it is of the skin, which has implications for a better understanding of the disease.

Epidemiology and clinical outcome of enterococcal bacteraemia in an acute care hospital

OBJECTIVE

To determine the epidemiology and clinical outcome of enterococcal bacteraemia in an acute care hospital.

MATERIALS AND METHODS

This is a retrospective study on enterococcal bacteraemia in an acute hospital from January 1999 to June 2001. Patients' clinical case notes were reviewed and their demographic, clinical and microbiological data were recorded.

RESULTS

A total of 42 patients (25 males and 17 females) were included in the study, their mean age was 74.8+/-10.9 years. The majority of them had underlying diabetes mellitus and neurological disease. Seventeen patients required intensive care. Sources of enterococcal bacteraemia were identified in 21 cases (urinary tract, 13 patients; hepatobiliary, five; cardiovascular, two and soft tissues, one patient). Eighteen patients had prior invasive procedures. All the Enterococcus species isolated were vancomycin-susceptible; however, eight were ampicillin-resistant and 13 had high-level gentamicin resistance. Shock, disseminated intravascular coagulopathy, acute renal failure and cardiorespiratory arrest occurred in 42% of the cases. Antibiotics were prescribed appropriately in 31 patients and seven deaths were recorded. Of the 11 patients who received inappropriate therapy, six deaths were recorded. Inappropriate antibiotic therapy was associated with mortality. The mortality rate was 31%. Only one patient had a relapse of enterococcal bacteraemia from urinary tract infection secondary to underlying ureteric stricture. There were no vancomycin resistant cases.

CONCLUSION

Urinary tract infection was the most common source of enterococcal bacteraemia. Appropriate antibiotics were essential in treating bacteraemia to reduce mortality. Vancomycin-resistant Enterococcus was not detected. The presence of comorbid conditions and invasive procedures in patients with enterococcal bacteraemia were found in 86 and 71% of patients, respectively.

Epithelioid trophoblastic tumor: a case report

Epithelioid trophoblastic tumor is a rare and distinctive pathologic entity within the complex family of gestational trophoblastic disease. We describe a case of epithelioid trophoblastic tumor occurring in a 34-year-old woman, who presented with a large uterine tumor 3 years following an uncomplicated pregnancy. The clinicopathologic findings in this case are typical of this unusual entity and consistent with current literature, with the exception of negative beta-human chorionic gonadotrophin levels. The distinguishing features from other intermediate trophoblastic tumors and tumor-like lesions are discussed.

Combined high-resolution magnetic resonance imaging and histological examination to explore the role of ligaments and tendons in the phenotypic expression of early hand osteoarthritis

BACKGROUND

The pathogenesis of the early stages of hand osteoarthritis is poorly understood, but recent high-resolution magnetic resonance imaging (hrMRI) studies suggest that the joint ligaments have a major role in the phenotypic expression of the disease.

OBJECTIVE

To combine hrMRI and cadaveric histological studies to better understand the mechanisms of damage, and especially the role of joint ligaments and tendons in disease expression.

METHODS

hrMRI was carried out in the distal interphalangeal (DIP) and proximal interphalangeal (PIP) joints in 20 patients with osteoarthritis, with a disease duration < or = 12 months. Histological sections of the DIP and PIP joints were obtained from three dissecting-room specimens for comparative analysis.

RESULTS

The collateral ligaments influenced the location of both hrMRI-determined bone oedema and bone erosion in early osteoarthritis. These changes were best understood in relation to the enthesis organ concept, whereby the interaction between ligament fibrocartilages leads to bone disease. Normal ligaments were commonly associated with microdamage at insertions corresponding to ligament thickening noted in early osteoarthritis. The ligaments also influenced the location of node formation in early osteoarthritis. The DIP extensor tendon insertions were associated with the development of a neoarticular surface.

CONCLUSIONS

Small-joint collateral ligaments and tendons have a central role in the early stages of hand osteoarthritis, and determine the early expression of both the soft tissue and bony changes in disease.

Infliximab in combination with methotrexate in active ankylosing spondylitis: a clinical and imaging study

OBJECTIVE

To examine the efficacy and safety of infliximab combined with methotrexate compared with methotrexate alone in the treatment of ankylosing spondylitis (AS) using MRI and DXA to monitor its impact on bone.

METHODS

In this single centre study 42 subjects with active AS were treated with methotrexate and were randomly assigned, in a ratio of 2:1, to receive five infusions of either 5 mg/kg infliximab or placebo over 30 weeks. The primary outcome was improvement in disease activity as shown by the BASDAI at week 30. MRI was used to assess the effect of treatments on sacroiliac and spinal enthesitis/osteitis and DXA to monitor bone mineral density.

RESULTS

Both therapeutic agents were well tolerated with no dropouts due to adverse events. A significantly greater improvement in mean BASDAI score was seen in the infliximab arm at week 10 (p = 0.017) than in the placebo arm, but this was not maintained by week 30 (p = 0.195), 8 weeks after the last infusion, at which stage disease flares were reported by some subjects. MRI showed that the mean number of lesions resolving for each subject from week 0 to week 30 was significantly greater in the combination group than in the methotrexate monotherapy group (p = 0.016).

CONCLUSIONS

Infliximab in combination with methotrexate was a safe and efficacious treatment in AS over 6 months and was associated with significant regression in enthesitis/osteitis as determined by MRI. However, disease flares were reported 8 weeks after the last infusion, indicating that addition of methotrexate failed to extend the infliximab dosing interval.

Influence of the amyloid precursor protein locus on dementia in Down syndrome

BACKGROUND

The amyloid precursor protein (APP) locus on chromosome 21 influences the development of Alzheimer disease.

METHOD

The authors investigated the relationship between a tetranucleotide repeat on intron 7 of the APP gene and the age at onset of dementia in Down syndrome (DS).

RESULTS

There was a 13-year difference in the age at onset of dementia in DS associated with the number of tetranucleotide repeat alleles in APP.

CONCLUSION

APP is an important locus predicting the age at onset of dementia in people with Down syndrome.

Efficacy of anakinra in active ankylosing spondylitis: a clinical and magnetic resonance imaging study

OBJECTIVE

To determine the efficacy of anakinra, an interleukin 1 receptor antagonist in active ankylosing spondylitis (AS), and to investigate the effect of anakinra treatment on spinal enthesitis/osteitis using magnetic resonance imaging (MRI).

METHODS

A 3 month open label study of anakinra (100 mg subcutaneous injection daily) was carried out in nine patients with active AS who had back pain and an increased acute phase response, and who had failed to respond to at least one non-steroidal anti-inflammatory drug. Clinical assessment included the Bath AS Functional Index (BASFI), Bath AS Disease Activity Index (BASDAI), and AS Quality of Life (ASQoL) before and after treatment. Fat suppressed MRI of the spine and sacroiliac joints was performed with a 1.5 T scanner at baseline and at 3 months to determine the effect of treatment on spinal enthesitis/osteitis.

RESULTS

Significant improvement was found in the BASFI (median baseline 5.88, 3 months 3.63, p = 0.021), BASDAI (median baseline 5.63, 3 months 3.48, p = 0.028), ASQoL (median baseline 12, 3 months 8, p = 0.011) and laboratory measures reflecting inflammation, with C reactive protein (median baseline 31 mg/l, 3 months 17 mg/l, p = 0.036) and erythrocyte sedimentation rate (median baseline 19 mm/1st h, 3 months 15 mm/1st h, p = 0.008) also showing significant improvement. Six patients (67%) achieved the Assessments in AS (ASAS) Working Group criteria of 20% improvement. Of the 38 regions of enthesitis/osteitis determined by MRI at baseline, 23 (61%) either improved or regressed completely.

CONCLUSIONS

This open label pilot study suggests that anakinra is effective in controlling the clinical manifestations of AS. The clinical response was reflected by an improvement in MRI determined spinal enthesitis/osteitis.

Prospective randomized study of bacteraemia in diathermy and stapled haemorrhoidectomy

BACKGROUND

The incidence and consequences of bacteraemia associated with diathermy and stapled haemorrhoidectomy have not been studied previously.

METHODS

Two hundred and five healthy patients randomized to stapled haemorrhoidectomy or diathermy haemorrhoidectomy had perioperative blood cultures taken. The clinical sequelae of bacteraemia and complications of surgery were assessed prospectively.

RESULTS

Six patients were excluded for protocol violations. Eleven (11 per cent) of 101 patients with stapled and five (5 per cent) of 98 who had diathermy haemorrhoidectomy had positive blood cultures for organisms after haemorrhoidectomy, predominantly anaerobes commonly found within the bacterial flora of the anorectum (P = 0.19). Transient postoperative pyrexia in several patients did not correlate with detected bacteraemia and settled spontaneously without treatment. There were no serious complications from either operative technique, and no clinical consequences from proven bacteraemia.

CONCLUSION

Transient bacteraemia may complicate surgical haemorrhoidectomy but has no serious clinical consequences for healthy adults.

Microbiology of chronic suppurative otitis media in Singapore

The objective of the study was to study the microflora and the antibiograms of patients with chronic suppurative otitis media (CSOM) in Singapore. Ninety patients with CSOM were prospectively studied. They had chronic ear discharge and had not received antibiotics for the previous five days. Swabs were taken, and cultured for bacteria. Antibiotic testing was done using modified Kirby Bauer disk diffusion method. In addition to the usual antibiotics, the three most common topically available antibiotics (chloramphenicol, gentamicin and neomycin) were tested. There were 135 positive cultures for organisms from the 90 patients. The most common causal organisms isolated were Pseudomonas aeruginosa (33.3%) and Staphylococcus aureus (33.3%) followed by coagulase negative Staphylococcus (21.1%). Fungi accounted for 8.8% of isolates while 6.6% were anaerobes. Of the three antibiotics commonly available as topical eardrops, gentamicin has the highest susceptibility rate (82.6%), followed by neomycin (67.8%) and chloramphenicol (62.8%).

Cryptococcus neoformans var. gattii meningitis in Singapore

We describe here two cases of Cryptococcus neoformans var. gattii meningitis that occurred in Singapore. This variety of Cryptococcus neoformans differs from the more widely known C. n. var. neoformans in its ecology and epidemiology. Infections with this variety are still rare in Singapore.

Shigella septicaemia in adults: report of two cases and mini-review

INTRODUCTION

We report 2 cases of Shigella septicaemia in adult patients.

CLINICAL PICTURE

Two 57-year-old women presented with non-bloody diarrhoea and fever. The first patient was an inmate of a long-term care facility who was schizophrenic and the second patient was a diabetic who recently travelled to Medan, Indonesia. Both patients were febrile, hypotensive and dehydrated. The first patient was neutropenic, thrombocytopenic and had acute renal failure. Blood cultures yielded Shigella flexneri and stool cultures gave negative results for both patients.

TREATMENT

Rehydration and intravenous ceftriaxone were instituted.

OUTCOME

The patients' symptoms and hypotension resolved.

CONCLUSION

Appropriate antibiotics can decrease the severity and duration of Shigella septicaemia.

Lung volume reduction surgery for the treatment of severe emphysema: a study in a single Canadian institution

OBJECTIVE

To evaluate lung volume reduction surgery (LVRS) and its effectiveness in improving pulmonary function, exercise capacity and quality of life in a population of emphysema patients referred to and screened in a single centre.

DESIGN

A prospective case series.

SETTING

A Canadian tertiary care hospital.

PATIENTS

Patients with severe emphysema, significant dyspnea and impaired exercise capacity interfering with quality of life.

INTERVENTIONS

Bilateral LVRS was performed through a median sternotomy.

MAIN OUTCOME MEASURES

Pulmonary function tests (preoperative forced expiratory volume in the first second [FEV1], residual volume [RV]), 6-minute walk (6 MW) distance, quality of life (Medical Outcomes Study 36-item short-form health survey) and degree of dyspnea (Medical Research Council of Great Britain dyspnea scale and the baseline and transitional dyspnea indices) were assessed before LVRS and at 6 and 12 months after.

RESULTS

Fifty-seven patients were assessed for LVRS, of whom 10 were selected for surgery. Homogeneous distribution of disease was the most common reason for exclusion. Of the 10 patients operated upon, 1 died of acute cor pulmonale on the fourth postoperative day and 1 died of recurrent exacerbations of chronic obstructive pulmonary disease and chronic respiratory failure at 315 days postoperatively. In the surviving patients, the mean preoperative FEV1 increased from 0.70 L before surgery to 0.90 L at 1 year, with a mean relative increase of 33.4%. The mean RV decreased from 5.57 L to 4.10 L, with a mean relative decrease of 27.6%. The 6 MW distance increased from 302.7 m to 356.9 m at 1 year, with a mean relative increase of 21.6%. Quality of life and degree of dyspnea were improved significantly at 1 year after LVRS. Of the 5 patients on oxygen at home before surgery, 4 were able to reduce their requirements but not to discontinue oxygen.

CONCLUSIONS

LVRS is an effective palliative treatment for dyspnea and poor exercise tolerance in highly selected patients. Although the duration of palliation is unknown, our results show that improvements in pulmonary function, exercise, quality of life and degree of dyspnea are preserved over the first year. Only a minority of the patients screened were eligible for surgery. The 2 deaths in our series emphasize the need for even further delineation of selection criteria.

Recurrence of Helicobacter pylori infection and duodenal ulcer relapse, following successful eradication in an urban east Asian population

We aimed to determine the rate of Helicobacter pylori (HP) recurrence and duodenal ulcer relapse in patients of a hospital in Singapore over a period of at least one year from the time of eradication. Ninety-six consecutive duodenal ulcer patients with biopsy-proven HP eradication and healed ulcer were seen at 3-month intervals, and follow-up endoscopy was performed when dyspepsia recurred, at the end of one year after eradication, or at the time of recall if the patient had been lost to follow-up. HP status was determined by antral and corpus biopsies and by antral cultures. Sixty-five had been given triple therapy, and 31 received dual therapy with omeprazole + amoxycillin or clarythromycin. Median time to follow-up endoscopy was 12 months. Six patients (6.25%) were positive for HP infection after eradication. Recurrence of HP infection was detected at 9 and 10 months after confirmation of HP eradication in two patients, and at between 13 and 20 months in the remaining four. Two of these had recurrent duodenal ulcer; all but one had erosive duodenitis. Two other patients had recurrent duodenal ulcer despite absence of HP reinfection; they admitted to taking low-dose aspirin. It was concluded that the recurrence of HP infection is low at the end of one year after successful eradication therapy in this urban East Asian population. Ulcer relapse occurred in 4.17% (4/96) of patients, and was associated with recurrent HP infection or NSAID exposure.

Audit of a multidisciplinary vulvar clinic in a gynecologic hospital

OBJECTIVE

To perform a five-year retrospective audit of all new patients referred to a tertiary vulvar referral service.

STUDY DESIGN

A review was made of the records of all new clients who attended the vulvar clinic between 1993 and 1997. Information was entered into a database and analyzed.

RESULTS

Four hundred seventeen women were seen in the study period. Their ages ranged from 8 to 94 years (mean, 48.5). The most common symptoms were pruritus (44.8%), soreness (28.6%) and irritation (24.2%). Striking features were the poorly defined and lengthy histories and multiple symptomatology. Biopsies were performed in 61% of cases. Histologic diagnoses included vulvar intraepithelial neoplasia (VIN), 18.5%; nonneoplastic epithelial disorders, 16.8%; and carcinoma, 8.1%. Clinical diagnoses included dermatitis in 10% and normal vulva in 7.7%. The remaining cases represented a wide variety of dermatologic, pain and gynecologic conditions. There was a 95% correlation between the clinical and histologic diagnosis of VIN and 87% in lichen sclerosus. In 64.7% of women, treatment resulted in an improved outcome, 13.7% reported no improvement, and 1.6% cases deteriorated during treatment; 19.9% were lost to follow-up.

CONCLUSION

Provision of a multidisciplinary vulvar clinic in a tertiary setting provides an invaluable service for both primary and secondary clinical practitioners. The increasing demand for our services has created lengthy waiting times. The chronic nature of many vulvar diseases results in long-term follow-up of many women. Patient selection bias has developed as a consequence of the interests of the clinicians involved.

Metronidazole-resistant Helicobacter pylori in an urban Asian population

BACKGROUND

Helicobacter pylori eradication is the mainstay in the treatment of H. pylori-associated peptic ulcer disease. Metronidazole is an important component in most eradication regimens. However, the presence of metronidazole-resistant H. pylori adversely affects the efficacy of such regimens. We aimed to study the prevalence of metronidazole resistance in our population, and the factors associated with its presence.

METHODS AND RESULTS

From September 1993 to September 1996, 459 H. pylori isolates were collected and analysed. The overall resistance rate was 62.7%. The rate was significantly higher among women compared with men (P < 0.05). When the results were analysed according to each year, there was a significant increase in the resistance rate from 50.5% in the first year to 72.7% in the third year (P = 0.0039).

CONCLUSIONS

There was a significant rise in the prevalence of metronidazole resistance over a 3-year period. The presence of metronidazole resistance adversely affects the eradication rates of nitroimidazole-based regimens. Hence, in a population with a high prevalence of metronidazole resistance, the use of non-nitroimidazole-based therapy may be more efficacious. This information on resistance rates is important for the empirical choice of antibiotic against H. pylori in a population.

Non-steroidal anti-inflammatory drugs, Helicobacter pylori and bleeding gastric ulcer

BACKGROUND

Helicobacter pylori infection and NSAID usage are considered to be independent risk factors for gastric ulcer (GU). Whether they interact to influence the risk of bleeding in GU is unclear.

AIM

To determine the prevalence of H. pylori infection and NSAID ingestion in a group of patients with GU and determine their roles in bleeding and non-bleeding GU.

METHODS AND RESULTS

From January 1993 to June 1996, a total of 217 GU patients (150 male, 67 female, median age 61 years, range 26-94) were eligible for the study. Eighty-five per cent were H. pylori-positive and 15% were H. pylori-negative. NSAID usage within 4 weeks prior to endoscopy was present in 30%, more in the H. pylori-negative than H. pylori-positive patients (59% vs. 25% P = 0.0002). Aspirin was most commonly used (43%). One hundred patients bled from GU (69 male, 31 female, mean age 67 years, range 26-94) and 117 did not (81 male, 36 female, mean age 57 years, range 28-86). Univariate logistic regression showed that advanced age (>/= 65 years) and NSAID usage carried an increased risk of bleeding GU (odds ratio 3.4 and 6.8, respectively) while H. pylori infection alone was not associated with additional risk (OR = 0.8). However, when three variables were considered jointly in a multiple logistic regression, the OR associated with H. pylori infection increased to 2.4, suggesting that in the presence of NSAIDs and advanced age, H. pylori also increases the risk of bleeding GU, indicating an interaction between the variables.

CONCLUSION

NSAID usage and advanced age are risk factors for bleeding GU, whereas H. pylori infection by itself is not. In the presence of NSAIDs and advanced age, an increased risk of bleeding GU with H. pylori is observed, indicating the possibility of an interaction between these factors.

Disseminated Penicillium marneffei infection: a report of five cases in Singapore

Penicillium marneffei has emerged as an important opportunistic pathogen in HIV-infected patients in Southeast Asia. We report the first 5 cases of P. marneffei diagnosed in Singapore. All the patients were HIV-infected and were either Thai nationals or had frequently travelled to Thailand. Fever, weight loss, anaemia and papular skin lesions were common clinical manifestations in our patients, all of whom had the organism isolated from blood. Skin biopsy specimens showed histological evidence of P. marneffei in 2 patients. In 1 patient each, the organism grew in cultures of specimens from bone marrow and respiratory secretions. Amphotericin B therapy followed by itraconazole were used in 3 of our 5 patients and was associated with good clinical response and outcome.

Corneal topography of small-beam tracking excimer laser photorefractive keratectomy

PURPOSE

To evaluate the topographic characteristic of photorefractive keratectomy (PRK) for low myopia performed with a small-beam (0.9 mm) tracking excimer laser.

SETTING

Department of Ophthalmology, LSU Eye Center, Louisiana State University Medical Center School of Medicine in New Orleans, and the Refractive Surgery Center of the South at the Eye, Ear, Nose, & Throat Hospital, New Orleans, Louisiana, USA.

METHODS

Sixty-seven eyes of 47 patients had PRK with a small-beam tracking laser. Of these, 49 eyes had data permitting evaluation of ablation centration; usable data for topographic analysis were available for 59 eyes preoperatively, 54 eyes at 1 month, 42 eyes at 3 months, and 25 eyes at 6 months, permitting measurement of various topographic parameters, including the cylinder (CYL), average corneal power (ACP), surface regularity index (SRI), surface asymmetry index (SAI), corneal eccentricity index (CEI), and coefficient of variation of corneal power (CVP).

RESULTS

Preoperatively, all eyes were topographically normal. Postoperatively, no eye exhibited a "central island" by even the least-restrictive definition, and all eyes had best spectacle-corrected visual acuities (BSCVAs) of 20/20 or better at all follow-ups. Mean decentration of the ablations from the pupil centers was 0.42 mm +/- 0.28 (SD) (n = 49). There was no correlation between measured decentration and BSCVA (P = .46). The central cornea was flattened (decreased ACP; P < .001) and made oblate (decreased CEI; P < .001) as expected. There was no increase in SRI or SAI (irregular astigmatism) at 6 months compared with preoperative values (P = .91); however, CYL and CVP (varifocality) increased slightly (P = .04 and .02, respectively).

CONCLUSION

The absence of significant regular or irregular astigmatism 6 months after PRK with the small-beam laser is an improvement over published results achieved with wide-beam lasers and is consistent with the excellent visual acuity results in this cohort.

Complexes of salicylaldehyde acylhydrazones: cytotoxicity, QSAR and crystal structure of the sterically hindered t-butyl dimer

A series of acylhydrazones of salicylaldehyde and their transition metal complexes, predominantly copper(II), have been prepared and characterized. The crystal structure of the Cu(II) complex of the sterically hindered t-butyl derivative contains a phenolato bridged dimer with the ligand coordinated as a tridentate moiety. QSAR analyses of the cytotoxicity of the chelators and their Cu(II) complexes reveals that solubility is the dominant factor for activity. Compounds display a maximum with respect to lipophilicity, allowing optimization of the bioactivity for both the ligands and their complexes. Copper complexes are significantly more cytotoxic than the metal-free ligands and complexes of other metals: Cu > Ni > Zn = Mn > Fe = Cr > Cr > Co.

In vivo confocal microscopy of Fuchs' endothelial dystrophy

PURPOSE

The purpose of this study is to analyze in vivo confocal microscopic findings of corneas with Fuchs' endothelial dystrophy.

METHODS

Central corneas of 17 eyes of 11 patients aged 41-86 years were examined using in vivo scanning slit confocal microscopy after being diagnosed with Fuchs' endothelial dystrophy. The cellular structure of the corneas was analyzed morphologically and quantitatively and compared to control results from 22 healthy corneas.

RESULTS

Bullae were detected in the basal epithelial layer of one eye. Eight of 17 eyes (47%) exhibited an abnormal Bowman's layer: diffuse bright reflection and absence of nerves. Eleven eyes (65%) exhibited abnormal anterior stroma: lacunae and diffuse increased light reflection due to edema. In 12 eyes (71%), lacunae or dark bands 5-20 microm wide against increased background reflection were noted in the posterior stroma. Descemet's membrane was thickened in all eyes. Dark bands were detected in six eyes (35%). Guttae (137-1,231/mm2) 20-40 microm in diameter were found in every endothelial cell layer. The mean endothelial cell count was 1,202 +/- 850 (cells/mm2 +/- SD; range, 0-2,735). There was a positive correlation between endothelial cell counts obtained by specular microscopy and those obtained by confocal microscopy (r = 0.95).

CONCLUSION

In vivo confocal microscopic findings of Fuchs' endothelial dystrophy are described for the first time in a series of cases. Pathological changes in Fuchs' dystrophy were detected in all corneal layers, more frequently in the posterior layers. Endothelial cell counts obtained with confocal microscopy were statistically similar to those obtained with standard specular microscopy.

Normal human corneal cell populations evaluated by in vivo scanning slit confocal microscopy

PURPOSE

To analyze cellular populations in healthy human corneas.

METHODS

The study group consisted of 58 eyes of 45 patients with normal corneas. The age distribution was 45 +/- 17 years (mean +/- SD; range, 20-84). Scanning slit confocal microscopy of the central corneas was performed. The images were analyzed visually for cell morphology, and the densities and areas of cells were measured.

RESULTS

No statistically significant differences were measured in cell densities or cell areas of any corneal layer between female and male patients (p = 0.22-0.50) nor between right and left eyes (p = 0.16-0.45). The area of superficial epithelial cells was 913 +/- 326 microm2 (mean +/- SD; range, 518-2,112), and the superficial epithelial cell density was 1,213 +/- 370 cells/mm2 (mean +/- SD; range, 473-1,929). The area of basal epithelial cells was 177 +/- 19 microm2 (mean +/- SD; range, 138-242), and the basal epithelial cell density was 5,699 +/- 604 cells/mm2 (mean +/- SD; range, 4,135-7,267). The average apparent keratocyte density was 1,058 +/- 217 cells/mm2 (mean +/- SD; range, 604-1,599) in the anterior stroma, and 771 +/- 135 cells/mm2 (mean +/- SD; range, 493-1,145) in the posterior stroma. The difference in apparent keratocyte densities between the anterior and posterior stroma was statistically significant (p < 0.001). The average endothelial cell area was 334 +/- 51 microm2 (range, 273-553), and the cell density was 3,055 +/- 386 cells/mm2 (mean +/- SD; range, 1,809-3,668). The endothelial cell density had a negative, statistically significant correlation with age (r = -0.68, p < 0.001). The densities of the other corneal cell layers did not have a statistically significant correlation with age.

CONCLUSION

In vivo scanning slit confocal microscopy is a useful tool for studying corneal cell populations. Central corneal cell densities were found to decrease significantly with age only in the endothelium. For the first time in human corneas using in vivo confocal microscopy, this study statistically confirms a higher apparent number of keratocytes in the anterior stroma than in the posterior stroma.

Structure—activity relationships of some indolo[3,2-c]quinolines with antimalarial activity

The synthesis, physicochemical characterization and in vitro antimalarial activity of a series of indolo[3,2-c]quinolines (9a-f) are described. There is only a poor correlation between the activity and hydrophobicity. In contrast, 33% of the observed variation in antimalarial activity can be attributed to the size of the side chain attached to position 9 of the indoloquinoline ring. An increase in the size of this dibasic side chain generally results in a reduction in activity, suggesting that it is accommodated in a site/cavity of limited size on the receptor. More significantly, the charge on the distal nitrogen (N3) on the side chain, located 10-11 A from the quinoline N, could account for 75% of the observed variation. Since a large charge on N3 is associated with improved antimalarial activity, it is suggested that N3 is protonated and functions as a H bond donor in the drug-receptor interaction.

Progression of vulvar intraepithelial neoplasia III to invasive carcinoma in a young woman

This case documents the progression of untreated vulvar intraepithelial neoplasia to invasion in a young woman over a four and a half year period. Conflicting views with regards to the natural history of VIN II are discussed.

Comparison of Pseudomonas pseudomallei from humans, animals, soil and water by restriction endonuclease analysis

Pseudomonas pseudomallei isolates from 62 human, 17 animal, 3 soil and 3 water samples were examined by genomic DNA digestion with PstI. Five major (RE I, II, III, IV, V) reproducible restriction patterns were observed, with most (56/62) of the human isolates displaying RE I (30/62), II (5/62), III (15/62), IV (4/62), V (2/62), and the animal (16/17), soil (2/3), water (3/3) isolates showing predominantly RE II profiles. Six human and one soil isolates showed patterns different from those of RE I to V. Restriction endonuclease analysis may be applied in epidemiological studies of melioidosis.

Bacteroides fragilis meningitis

Bacteroides fragilis is an obligate anaerobic bacillus residing in the normal intestinal flora of the colon. Anaerobic bacterial meningitis due to this pathogen is rarely diagnosed and if present, a predisposing source of infection should be actively sought for. Anaerobic cultures of cerebrospinal fluids should be done for patients with meningitis, especially those with concomitant pathologies that predispose to anaerobic infections. Two cases of anaerobic meningitis due to Bacteroides fragilis, one associated with cholesteotoma and the other with nasopharyngeal carcinoma, are reported. Both were successfully treated with metronidazole.

Clotest (rapid urease test) in the diagnosis of Helicobacter pylori infection

Over a period of 3 months, 85 patients who underwent gastroscopy had antral biopsy taken for Clotest, histology and/or culture for Helicobacter pylori (HP). The sensitivity and specificity of Clotest were found to be 77% and 96% respectively with negative predictive value of 63% and positive predictive value of 98%. Ninety-two percent of the positive Clotests were positive within 20 minutes, thus giving rapid result. Therefore, Clotest is a rapid, sensitive and highly specific test for HP infection. A high correlation between HP infection and chronic gastritis was noted and the prevalence of HP infection in patients with duodenal ulcer (90%) was higher than that of gastric ulcer (64%) or non-ulcer group (65%).

Renal tubular function of cadmium exposed workers

The kidney is considered the critical organ following long term occupational or environmental exposure to cadmium. Tubular dysfunction in the form of low molecular weight proteinuria is the earliest manifestation of cadmium nephrotoxicity. The current acceptable critical concentration of cadmium in the urine is 10 ug Cd/g creatinine. The aim of this paper is to identify the presence of tubular dysfunction among workers with less than 10 ug Cd/g creatinine. The exposed group of 92 workers were from a nickel-cadmium battery factory. The control group of 122 workers were factory and sedentary office workers with no known history of exposure to nephrotoxic agents. The urinary excretion of N-acetyl-D-glucosaminidase (NAG), beta-2-microglobulin (beta 2m) and alpha-1-microglobulins (alpha 1m) were measured from morning spot urine samples. The age, sex and race adjusted NAG and alpha 1m showed increasing trend with rising urinary cadmium levels. Levels were significantly raised when the urinary cadmium was above 5 ug Cd/g creatinine. A similar trend was seen with increasing length of exposure. Renal tubular dysfunction is present among cadmium exposed workers with levels below the current critical concentration.