Epstein-Barr virus DNA monitoring in serum and whole blood in pediatric liver transplant recipients who do or do not discontinue immunosuppressive therapy

The rate of PTLD can be reduced by weaned IS guided by monitoring of EBV DNA. In this single-center retrospective case series study, we analyzed how reduction in IS influenced EBV DNA levels in whole blood and serum in 30 children during the first year after liver transplantation, and how these levels were related to symptoms putatively due to EBV. Primary and reactivated EBV infection was seen in 18 (60%) and eight patients (27%), respectively. Thirteen patients (42%) developed chronic high load the first year post-transplant. IS was successfully discontinued in six patients the first year post-transplant and in another two patients within 3 years. EBV DNA levels were reduced, but persisted long term in all the eight patients who had IS completely withdrawn. There was no case of PTLD. In summary, EBV DNAemia and chronic high load were very common after pediatric liver transplantation. Liver graft tolerance facilitates radical reduction in IS treatment, which may prevent PTLD, but EBV DNAemia may persist long term after discontinued IS.

Utility of oropharyngeal real-time PCR for S. pneumoniae and H. influenzae for diagnosis of pneumonia in adults

A lack of sensitive tests and difficulties obtaining representative samples contribute to the challenge in identifying etiology in pneumonia. Upper respiratory tract swabs can be easily collected and analyzed with real-time PCR (rtPCR). Common pathogens such as S. pneumoniae and H. influenzae can both colonize and infect the respiratory tract, complicating the interpretation of positive results. Oropharyngeal swabs were collected (n = 239) prospectively from adults admitted to hospital with pneumonia. Analysis with rtPCR targeting S. pneumoniae and H. influenzae was performed and results compared with sputum cultures, blood cultures, and urine antigen testing for S. pneumoniae. Different Ct cutoff values were applied to positive tests to discern colonization from infection. Comparing rtPCR with conventional testing for S. pneumoniae in patients with all tests available (n = 57) resulted in: sensitivity 87 %, specificity 79 %, PPV 59 % and NPV 94 %, and for H. influenzae (n = 67): sensitivity 75 %, specificity 80 %, PPV 45 % and NPV 94 %. When patients with prior antimicrobial exposure were excluded sensitivity improved: 92 % for S. pneumoniae and 80 % for H. influenzae. Receiver operating characteristic curve analysis demonstrated for S. pneumoniae: AUC = 0.65 (95 % CI 0.51-0.80) and for H. influenzae: AUC = 0.86 (95 % CI 0.72-1.00). Analysis of oropharyngeal swabs using rtPCR proved both reasonably sensitive and specific for diagnosing pneumonia caused by S. pneumoniae and H. influenzae. This method may be a useful diagnostic adjunct to other methods and of special value in patients unable to provide representative lower airway samples.

Peripheral arterial disease. Contrast-enhanced 3D MR angiography of the lower leg and foot compared with conventional angiography

Purpose: To determine whether contrast-enhanced 3D MR angiography (CE MRA) could replace digital subtraction angiography (DSA) for the evaluation of atherosclerotic peripheral vascular disease of the lower leg and foot.

Material and Methods: Thirty-five patients with symptoms of atherosclerotic disease of the leg were examined prospectively with CE MRA of the foot and the lower legs as well as with DSA from the aorta to the pedal arches. The MRA technique was focused on optimal imaging of the arteries of the foot.

Results: The agreement between CE MRA and DSA for grading of stenosis was moderate to good (weighted κ-values 0.48–0.80). The sensitivity of CE MRA for detection of significant stenosis (≥ 50%) was 92% and the specificity was 64% with DSA as gold standard.

Conclusion: CE MRA is a fairly accurate method for the demonstration of atherosclerotic disease below the knee including the pedal arches. It can replace DSA for the assessment of distal arteries in patients with impaired renal function. However, image quality and resolution still needs to be improved before CE MRA can become the method of choice in all patients.

Endovascular Stent-Anchored Aortic Grafts: A Comparison between Self-Expanding and Balloon-Expandable Stents in Minipigs

Purpose:

To study endovascular graft attachment with self-expanding Gianturco Z-stents and balloon-expanded Palmaz stents and the effect of these devices on the renal ostia.

Methods:

Ten stent-grafts were constructed, 5 with Gianturco Z-stents and 5 with Palmaz stents. The endografts were implanted under fluoroscopic guidance into the abdominal aorta of 10 pigs so that the uncovered portion of the proximal stent extended over the renal artery orifices. Distal aortic blood pressure and flow were measured before and after graft placement and 1 hour postprocedure. The aorta was then exposed surgically, and the central portion of the stent-graft was inspected through an aortotomy to assess perigraft leakage.

Results:

Stent-graft implantation was accurate and hemostatic in all cases, despite longitudinal folding of the graft due to oversizing. However, transverse folds produced pressure gradients (> 15 mmHg) between the ends of the graft in two cases. In another case, a pressure gradient resulted from partial thrombosis of the graft. In two cases, renal artery occlusion and thrombosis occurred due to coverage by the graft material. In two other animals, one of the renal arteries was entirely uncovered by a stent. The remaining 16 renal arteries were covered by the proximal stent but not the graft, as intended. One (6.25%) of these arteries thrombosed, but the remainder were grossly patent when the animals were sacrificed at 1 hour.

Conclusions:

Both Palmaz and Gianturco Z-stents produced hemostatic endovascular graft attachment, even in the presence of moderate graft oversizing. The risk of acute renal artery occlusion from juxtarenal stenting does not appear to be prohibitive, but longer term observations are needed.

Abdominal Aortic Aneurysm Morphology in Candidates for Endovascular Repair Evaluated with Spiral Computed Tomography and Digital Subtraction Angiography

Purpose:

To analyze the morphology of abdominal aortic aneurysms (AAAs) and to study the usefulness of spiral computed tomography (CT) versus digital subtraction angiography (DSA) in the evaluation of patients for endovascular repair.

Methods:

Of 133 AAA patients (120 men, mean age 67 years, range 52 to 84) evaluated preoperatively with CT imaging, 77 endograft candidates (68 men) were also assessed with intra-arterial DSA. Arterial parameters were measured on axial CT scans and angiographic films for comparison.

Results:

Mean maximum AAA diameter was 58 ± 11 mm (range 39 to 95). Aneurysmal neck diameter was consistently smaller on DSA than on CT (20.7 ± 3.6 mm versus 23.0 ± 3.5 mm, p < 0.0001). The distance from the most distal renal artery to the aortic bifurcation was longer on angiography than on CT (mean difference 10.0 mm, p < 0.0001). There was a positive correlation between the maximum AAA diameter and the AAA length (r = 0.49, p < 0.0001) and an inverse relationship between the neck length and the neck diameter (r = −0.36, p < 0.0001). No correlation was found between the maximum AAA diameter and maximum iliac diameter, angulation, or length.

Conclusions:

AAA anatomy varies widely and independently of the aneurysm size. Therefore, the maximum size of the aneurysm is a poor predictor of whether or not an aneurysm is suitable for endovascular repair. The discrepancy between angiographic and axial CT measurements suggests that neither alone is sufficient as a preoperative imaging technique when evaluating a patient for an endovascular graft procedure.

Endovascular AAA Exclusion: Will Stents with Hooks and Barbs Prevent Stent-Graft Migration?

Purpose:

To investigate if stents with hooks and barbs will improve stent-graft fixation in the abdominal aorta.

Methods:

Sixteen- to 24-mm-diameter Dacron grafts were deployed inside cadaveric aortas. The grafts were anchored by stents as in endovascular abdominal aortic aneurysm repair. One hundred thirty-seven stent-graft deployments were carried out with modified self-expanding Z-stents with (A) no hooks and barbs (n = 75), (B) 4 5-mm-long hooks and barbs (n = 39), (C) 8 10-mm-long, strengthened hooks and barbs (n = 19), or (D) hooks only (n = 4). Increasing longitudinal traction was applied to determine the displacement force needed to extract the stent-grafts. The radial force of the stents was measured and correlated to the displacement force.

Results:

The median (interquartile range) displacement force needed to extract grafts anchored by stent A was 2.5 N (2.0 to 3.4), stent B 7.8 N (7.4 to 10.8), and stent C 22.5 N (17.1 to 27.9), p < 0.001. Both hooks and barbs added anchoring strength. During traction, the weaker barbs were distorted or caused intimal tears. The stronger barbs engaged the entire aortic wall. The radial force of the stents had no impact on fixation, while aortic calcification and graft oversizing had marginal effects.

Conclusions:

Stent barbs and hooks increased the fixation of stent-grafts tenfold, while the radial force of stents had no impact. These data may prove important in future endograft development to prevent stent-graft migration after aneurysm exclusion.

Abdominal Aortic Aneurysms: Experience with the Ivancev-Malmö Endovascular System for Aortomonoiliac Stent-Grafts

Purpose:

To describe a component-based aortomonoiliac stent-graft system and the first clinical results achieved with this device in endovascular abdominal aortic aneurysm (AAA) repair.

Methods:

From November 1993 to October 1996, 45 patients aged 60 to 86 years underwent endoluminal exclusion of true AAAs (median diameter 60 mm) involving the common iliac arteries (median diameter 16 mm right and 15 mm left) using unilimb stent-grafts deployed with the Ivancev-Malmö system.

Results:

Six immediate conversions occurred in the beginning of the series due to endografts that were too short. Complications, including 2 inadvertent renal artery occlusions, 7 kinked grafts, 6 iliac artery dissections, and 3 perioccluder leaks, were prominent features in the first 15 patients. Five patients died in the postoperative period, four of whom were nonsurgical candidates. There were five significant stent-graft migrations: one 3 weeks after surgery due to mechanical injury of the proximal stent and four after 1 year owing to continuous dilation of a wide proximal neck, stent-graft placement in a conical, thrombus-lined proximal neck, and two instances of proximal extension separation from the main graft. Translumbar aneurysm perfusion required embolization in 3 patients.

Conclusions:

Despite early complications associated with a learning curve, exclusion of large AAAs using unilimb stent-grafts is feasible. Strict inclusion criteria are necessary in order to improve mortality among nonsurgical candidates and minimize the risk for late migration.

The aetiology of pharyngotonsillitis in adolescents and adults - Fusobacterium necrophorum is commonly found

Sore throat is common in primary healthcare. Aetiological studies have focused on the presence of a limited number of pathogens. The aim of the present study was to investigate the presence of a wide range of bacteria and viruses, including Fusobacterium necrophorum, in patients with pharyngotonsillitis and in asymptomatic controls. A prospective case control study was performed in primary healthcare in Kronoberg County, Sweden. Patients (n=220) aged 15 to 45 years with a suspected acute pharyngotonsillitis, and controls (n=128), were included. Nasopharyngeal and throat swabs were analysed for β-hemolytic streptococci, F. necrophorum, Mycoplasma pneumoniae, and Chlamydophila pneumoniae, and 13 respiratory viruses. Serum samples were analysed for antibodies to Epstein-Barr virus. The patient history and symptoms, including Centor score, were analysed in relation to pathogens. In 155/220 (70.5%) of the patients, as compared to 26/128 (20.3%) of the controls (p <0.001), at least one microorganism was found. Group A streptococci, F. necrophorum, and influenza B virus were the three most common findings, and all significantly more common in patients than in controls (p <0.001, p 0.001, and p 0.002, respectively). Patients with F. necrophorum only (n=14) displayed a lower Centor score than patients with Group A streptococcus only (n=46), but a higher score than patients with influenza B, other viruses, or no potential pathogen (Kruskal-Wallis p <0.001). A pathogen was detected in 70% of the patients, displaying a wide range of pathogens contributing to the aetiology of pharyngotonsillitis. This study supports F. necrophorum as one of the pathogens to be considered in the aetiology of pharyngotonsillitis.

Diarrhoeagenic microbes by real-time PCR in Rwandan children under 5 years of age with acute gastroenteritis

Acute gastroenteritis is a main cause of disease and death among children in low-income countries. The causality rates and pathogenic characteristics of putative aetiological agents remain insufficiently known. We used real-time PCR targeting 16 diarrhoeagenic agents to analyse stool samples from children ≤5.0 years old with acute diarrhoea in Rwanda. Among the 880 children (median age 14.2 months; 41% female) at least one pathogen was detected in 92% and two or more agents in 63% of cases. Rotavirus was detected in 36.9%, adenovirus in 39.7%, enterotoxigenic Escherichia coli (ETEC) with genes for labile (eltB) or stable (estA) toxin in 31.3% and 19.0%, E. coli with eae or bfpA genes in 25.2% and 14.2%, Shigella in 17.5% and Cryptosporidium in 7.8%. Rotavirus and ETEC-estA were associated with more severe dehydration than diarrhoea due to other causes. Shigella was associated with bloody stools and higher CRP. Microbial loads (Ct values) of rotavirus, ETEC-estA and Shigella were associated with severity of symptoms. Rotavirus, ETEC-estA and E. coli with bfpA were associated with younger age, Shigella with older age. Antibiotic treatment was given to 42% and was associated with dehydration, fever and CRP, but not with pathogen. We conclude that rotavirus and ETEC-estA were the most important causes of diarrhoea with dehydration, that Shigella caused bloody diarrhoea but less severe dehydration, that microbial loads of rotavirus, ETEC-estA and Shigella were associated with severity of symptoms, and that antibiotic use was frequent and in poor agreement with microbiological findings.

Dynamic tailoring of treatment durations improves efficiency of hepatitis C treatment with pegylated interferon and ribavirin

The treatment durations for hepatitis C are guided by the analysis of hepatitis C virus (HCV) RNA in blood at certain time points. This multicentre, randomized open label trial evaluated the utility and performance of individualized treatment durations guided by viral decline rates in 103 patients with HCV genotype 1 infection. Pegylated interferon 2a and ribavirin were given as standard of care (SOC) for 24, 48 or 72 weeks or as dynamic treatment (DT) for 24-72 weeks. The DT duration was based on the time point when log HCV RNA would reach 0 log copies/mL, as estimated by the second-phase decline. The rate of sustained virologic response was 63% for SOC and 54% for DT, but this difference was not significant in multiple regression analysis taking predictive factors such as interleukin-28B genotypes, age and baseline viremia into account (P = 0.45). The mean required treatment time per cured patient was 51 weeks for DT as compared with 58 weeks for SOC (P = 0.22) when given per protocol (n = 95) and was significantly shorter (42 vs 51 weeks) among patients who achieved undetectable HCV RNA (P = 0.01). We conclude that DT was feasible and increased efficiency. The estimated time point for 0 log viral copies/mL is a new and quantitative response variable, which may be used as a complement to the qualitative variable rapid virologic response. The outcome parameter treatment weeks per cured patient could become a useful tool for comparing treatment efficiency also in the era of directly acting antivirals.

Rhinovirus infections in western Sweden: a four-year molecular epidemiology study comparing local and globally appearing types

Human rhinovirus (HRV) is a highly prevalent pathogen and a major cause of acute respiratory tract infection (ARTI). HRV express less seasonality than other viral ARTIs, which typically appear as seasonal epidemics lasting for 1–2 months. The aim of this study was to investigate the seasonal patterns of HRV types over four consecutive years in one geographic region. HRV identified in respiratory samples from 114 patients over a four-year period were analysed by VP4/VP2 sequencing. HRV-A was found in 64, HRV-B in 11 and HRV-C in 37 cases. Overall, 33 different HRV-A types, nine B types and 21 C types were found. As many as 21 of the HRV types appeared during several seasons, with a maximum time-span of four years. Some types appeared during successive seasons and, in some cases, phylogenetic analysis indicated extended periods of circulation locally. Most of the strains were closely related to HRV identified in other parts of the world during the same time period. HRV strains that circulate locally represent many types and seem to reflect that HRV infections are highly globalised. The existence of simultaneous or successive epidemics with different HRV types in combination with the ability of each type to remain in the local population over extended periods of time may contribute to explaining the high rate of HRV infections.

IL28B polymorphisms determine early viral kinetics and treatment outcome in patients receiving peginterferon/ribavirin for chronic hepatitis C genotype 1

Single nucleotide polymorphisms (SNPs) upstream of IL28B predict the outcome of treatment in chronic hepatitis C virus (HCV) infection, but their impact on viral kinetics and relation to other predictors are not well known. Here, two SNPs, rs12979860 and rs8099917, were analysed and related to early viral kinetics during treatment in 110 patients with HCV genotype 1 infection. The reduction of HCV RNA after 7 days of therapy was more pronounced (P < 0.0001) in patients with CC(rs12979860) or TT(rs8099917) than in patients carrying TT(rs12979860) or GG(rs8099917), respectively. The two SNPs were in linkage disequilibrium (d' = 1, r2 = 0.44), but CC(rs12979860) was less common (43% vs. 71%) than TT(rs8099917). Patients carrying both CC(rs12979860) and TT(rs8099917) genotypes achieved lower levels of HCV RNA at week 4 than those with CT or TT at rs12979860 and TT(rs8099917) (P = 0.0004). The viral elimination was significantly influenced by rs12979860 independently of baseline viral load, age or fibrosis. This translated into high rates of sustained viral response (SVR) among patients carrying CC(rs12979860) despite the presence of high viral load at baseline (SVR 74%), high age (SVR 79%) or severe liver fibrosis (SVR 83%). We conclude that the IL28B variability influences the antiviral efficiency of interferon/ribavirin therapy and has a strong impact on SVR, independently of traditional response predictors. A combined assessment of these SNPs in conjunction with other response predictors may better predict outcome in difficult-to-treat patients.

High cytokine levels in perforated acute otitis media exudates containing live bacteria

Acute otitis media (AOM) is an inflammatory response to microbes in the middle ear, sometimes associated with rupture of the tympanic membrane. Human leukocytes produce different patterns of inflammatory mediators in vitro when stimulated with Gram-positive and Gram-negative bacteria, respectively. Here, we investigated the cytokine and prostaglandin E2 (PGE2) responses in middle ear fluids (MEFs) from children with spontaneously perforated AOM, and related the mediator levels to the presence of pathogens detected by culture (live) or PCR (live or dead). Furthermore, the in vivo cytokine pattern was compared with that induced in leukocytes stimulated by dead bacteria in vitro. MEFs with culturable pathogenic bacteria contained more interleukin (IL)-1β (median: 110 μg/L vs. <7.5 μg/L), tumour necrosis factor (TNF) (6.3 μg/L vs. <2.5 μg/L), IL-8 (410 μg/L vs. 38 μg/L) and IL-10 (0.48 μg/L vs. <0.30 μg/L) than culture-negative fluids, irrespective of PCR findings. IL-6 and PGE2 were equally abundant (69-110 μg/L) in effusions with live, dead or undetectable bacteria. Cytokine levels were unrelated to bacterial species and to the presence or absence of virus. Similar levels of TNF and IL-6 as found in the MEFs were obtained by in vitro stimulation of leukocytes, whereas 11 times more IL-1β and 3.5 times more IL-8 were produced in vivo, and 22 times more IL-10 was produced in vitro. Vigorous production of proinflammatory cytokines accompanies AOM with membrane rupture, regardless of the causative agent, but the production seems to cease rapidly once the bacteria are killed and fragmented. IL-6 and PGE2, however, remain after bacterial disintegration, and may play a role in the resolution phase.

High cytokine levels in perforated acute otitis media exudates containing live bacteria

Acute otitis media (AOM) is an inflammatory response to microbes in the middle ear, sometimes associated with rupture of the tympanic membrane. Human leukocytes produce different patterns of inflammatory mediators in vitro when stimulated with Gram-positive and Gram-negative bacteria, respectively. Here, we investigated the cytokine and prostaglandin E2 (PGE2) responses in middle ear fluids (MEFs) from children with spontaneously perforated AOM, and related the mediator levels to the presence of pathogens detected by culture (live) or PCR (live or dead). Furthermore, the in vivo cytokine pattern was compared with that induced in leukocytes stimulated by dead bacteria in vitro. MEFs with culturable pathogenic bacteria contained more interleukin (IL)-1β (median: 110 μg/L vs. <7.5 μg/L), tumour necrosis factor (TNF) (6.3 μg/L vs. <2.5 μg/L), IL-8 (410 μg/L vs. 38 μg/L) and IL-10 (0.48 μg/L vs. <0.30 μg/L) than culture-negative fluids, irrespective of PCR findings. IL-6 and PGE2 were equally abundant (69-110 μg/L) in effusions with live, dead or undetectable bacteria. Cytokine levels were unrelated to bacterial species and to the presence or absence of virus. Similar levels of TNF and IL-6 as found in the MEFs were obtained by in vitro stimulation of leukocytes, whereas 11 times more IL-1β and 3.5 times more IL-8 were produced in vivo, and 22 times more IL-10 was produced in vitro. Vigorous production of proinflammatory cytokines accompanies AOM with membrane rupture, regardless of the causative agent, but the production seems to cease rapidly once the bacteria are killed and fragmented. IL-6 and PGE2, however, remain after bacterial disintegration, and may play a role in the resolution phase.

Hepatitis C treatment response kinetics and impact of baseline predictors

The optimal duration of treatment for hepatitis C virus (HCV) infections is highly variable but critical for achieving cure (sustained virological response, SVR). We prospectively investigated the impact of age, fibrosis, baseline viraemia and genotype on the early viral kinetics and treatment outcome. Patients treated with peginterferon alfa-2a and ribavirin in standard dosing were included: 49 with genotype 1 treated for 48weeks and 139 with genotype 2 or 3 treated for 24weeks. The reduced SVR rates in patients older than 45years, with severe liver fibrosis or pretreatment viraemia above 400,000IU/mL were strongly associated with slower second phase declines of HCV RNA. Genotype 2/3 infections responded more rapidly than genotype 1, reaching week 4 negativity (RVR) in 59%vs 22%. We conclude that baseline response predictors such as age, fibrosis and viral load were well reflected by the early viral kinetics as assessed by repeated HCV RNA quantifications. The kinetic patterns and the high relapse rate in genotype 2/3 patients without RVR suggest that this group might benefit from treatment durations longer than 24weeks.

A variety of respiratory viruses found in symptomatic travellers returning from countries with ongoing spread of the new influenza A(H1N1)v virus strain

Clinical specimens from 79 symptomatic individuals with a recent history of travel to countries with verified transmission of influenza A(H1N1)v (North America) were tested with a multiple real-time PCR targeting a broad range of agents that may cause acute respiratory infection. This analysis revealed that besides four cases of influenza A(H1N1)v, other respiratory viruses were diagnosed in almost 60% of the samples. These observations are a reminder that many different viral transmissions occur simultaneously in countries with ongoing spread of influenza A(H1N1)v. The findings demonstrate that the definition of suspected cases by clinical and epidemiological criteria has only a poor capacity for discriminating influenza A(H1N1)v from other viral infections.

Are adjunctive markers useful in routine cervical cancer screening? Application of p16(INK4a) and HPV-PCR on ThinPrep samples with histological follow-up

The objectives of the study were to evaluate 1) the diagnostic sensitivity and specificity of p16(INK4a) as a marker for high-grade cervical lesions, 2) the results of a real-time polymerase chain reaction detecting high-risk human papillomavirus, and 3) the interobserver variability of the p16(INK4a) interpretation.A total of 232 ThinPrep samples were stained for p16(INK4a), and HPV-DNA PCR was performed on 107 specimens with inclusion of both benign and abnormal cytology. Histological follow-up information was collected. The diagnostic sensitivity of ASC+ with CIN2+ in histology as endpoint was 96% for p16(INK4a) and 100% for HR-HPV DNA PCR, and the diagnostic specificity was 41% and 27%, respectively. If p16(INK4a) had been used for triage of the ASC samples, then 18 patients (42%) could have been spared unnecessary follow-up procedures compared to six patients (21%) with the HR-HPV DNA test.

Comparison of HIV-1 pol and env sequences of blood, CSF, brain and spleen isolates collected ante-mortem and post-mortem

OBJECTIVES

HIV-1 infects the central nervous system (CNS) early in the course of infection. However, it is not known to what extent the virus evolves independently within the CNS and whether the HIV-RNA in cerebrospinal fluid (CSF) reflects the viral population replicating within the brain parenchyma or the systemic infection. The aim of this study was to investigate HIV-1 evolution in the CNS and the origin of HIV-1 in CSF.

MATERIALS AND METHODS

Longitudinally derived paired blood and CSF samples and post-mortem samples from CSF, brain and spleen were collected over a period of up to 63 months from three HIV-1 infected men receiving antiretroviral treatment and presenting with symptoms of AIDS dementia complex (ADC).

RESULTS

Phylogenetic analyses of HIV-1 V3, reverse transcriptase (RT) and protease sequences from patient isolates suggest compartmentalization with distinct viral strains in blood, CSF and brain. We found a different pattern of RT and accessory protease mutations in the systemic infection compared to the CNS.

CONCLUSIONS

We conclude that HIV-1 may to some extent evolve independently in the CNS and the viral population in CSF mainly reflects the infection in the brain parenchyma in patients with ADC. This is of importance in understanding HIV pathogenesis and can have implications on treatment of HIV-1 patients.

The perception of pain and pain-related cognitions in subacute whiplash-associated disorders: its influence on prolonged disability

PURPOSE

To clarify the relations between the sensory, affective and cognitive dimensions of pain and to analyse what influence these components have on persistent disability in patients with subacute whiplash-associated disorders (WAD).

METHOD

The data was obtained from an on-going randomised controlled trial (RCT) on 47 patients. The sensory dimension of pain was evaluated with a visual analogue scale (VAS) diary and a Painometer. The affective dimension was assessed using the Painometer. The Tampa Scale for Kinesiophobia (TSK) and the Self-Efficacy Scale (SES) were used as measures of pain-related cognitions. The Pain Disability Index (PDI) was used as the outcome measure.

RESULTS

Forty patients (85%) completed the trial. The correlations between the sensory and affective dimensions of pain were non-significant, which indicates that they are two independent constructs that describe various dimensions of whiplash-related pain. High pain intensity and pain affect, more widespread pain, and high fear of movement/(re)injury corresponded to low self-efficacy. Multiple regression analyses showed that self-efficacy was the most important predictor of persistent disability contributing to 42% of the variation in the PDI score.

CONCLUSION

The treatment approach for patients with subacute WAD should incorporate the multidimensional nature of pain and to prevent disability special effort should be made to enhance the patient's self-efficacy beliefs.

Endovascular Recanalisation in Occlusive Mesenteric Ischemia—Feasibility and Early Results

OBJECTIVE

To evaluate a single centre experience of endovascular treatment of mesenteric ischemia caused by vascular occlusion.

DESIGN

Retrospective study.

MATERIAL AND METHODS

Between 1995 and 2002 17 patients (12 females; mean age 61 years) with symptoms of bowel ischemia were treated endovascularly for arterial occlusion. Vessels were evaluated with angiography and pressure gradient measured. A mean gradient of > 20 mmHg or a stenosis of > 50% was considered significant. Patient data were recorded prospectively and follow-up was supplemented with retrospective chart review. Fifteen patients had follow up imaging, median 10 months (3-29 months) postoperatively. Median clinical follow up was 14 months (5-42 months).

RESULTS

Recanalisation was successful in 16 patients (94%). The average number of stents used was 1.6 per patient. For one patient recanalisation failed with subsequent SMA dissection. A celiac artery stenosis was stented but symptoms remained postoperatively. Perioperative mortality was 5.8% (n = 1). 14/17 patients (82%) displayed symptom relief/improvement. Six patients required secondary endovascular intervention; PTA (n = 3); stent/stentgraft (n = 3). Two of these patients required a third procedure. 4/6 patients that underwent secondary intervention were asymptomatic and of recurrent stenosis > 75% and a gradient > 15 mmHg mean pressure gradient on imaging. Two patients were treated because of a combination of angiographic findings and/or significant pressure gradient combined with clinical symptoms.

CONCLUSIONS

Endovascular treatment of mesenteric ischemia due to vessel occlusion is feasible with acceptable short-term results and limited complications. Most patients experience relief/improvement of symptoms. A significant number of patients might need endovascular re-intervention because of restenosis.

Peripheral arterial disease. Contrast-enhanced 3D MR angiography of the lower leg and foot compared with conventional angiography

PURPOSE

To determine whether contrast-enhanced 3D MR angiography (CE MRA) could replace digital subtraction angiography (DSA) for the evaluation of atherosclerotic peripheral vascular disease of the lower leg and foot.

MATERIAL AND METHODS

Thirty-five patients with symptoms of atherosclerotic disease of the leg were examined prospectively with CE MRA of the foot and the lower legs as well as with DSA from the aorta to the pedal arches. The MRA technique was focused on optimal imaging of the arteries of the foot.

RESULTS

The agreement between CE MRA and DSA for grading of stenosis was moderate to good (weighted kappa-values 0.48-0.80). The sensitivity of CE MRA for detection of significant stenosis (> or = 50%) was 92% and the specificity was 64% with DSA as gold standard.

CONCLUSION

CE MRA is a fairly accurate method for the demonstration of atherosclerotic disease below the knee including the pedal arches. It can replace DSA for the assessment of distal arteries in patients with impaired renal function. However, image quality and resolution still needs to be improved before CE MRA can become the method of choice in all patients.

Simple method for detection of mutations causing hereditary fructose intolerance

Aldolase B is critical for sugar metabolism, and a catalytic deficiency due to mutations in its gene may result in hereditary fructose intolerance (HFI) syndrome, with hypoglycaemia and severe abdominal symptoms. This report describes two cases of HFI, which were identified by intravenous fructose tolerance test and a new RFLP (restriction fragment length polymorphism) test that detects the two most common mutations, A149P and A174D. The method includes PCR of a 224-base-pair segment of exon 5, a subsequent 3 h incubation with Cac8I and agarose electrophoresis, which reveals either or both of the mutations in one single reaction. The method might be useful for screening of these mutations, which may account for more than 70% of the mutations causing HFI.

Moderate alcohol intake increases fibrosis progression in untreated patients with hepatitis C virus infection

Although excessive alcohol consumption in combination with hepatitis C virus (HCV) infection is known to increase the risk of liver cirrhosis, the effect of moderate alcohol intake remains to be elucidated. The aim of this study was to evaluate the effect of moderate alcohol consumption on fibrosis progression in HCV infection. A group of 78 patients with HCV infection and moderate alcohol consumption were analysed retrospectively. All patients had undergone two liver biopsies, with a median time between biopsies of 6.3 years, and had not received any antiviral therapy. Their lifetime drinking history was recorded. All patients except one had daily alcohol consumption below 40 g of ethanol (median 4.8 g/day, interquartile range 1.1-11.6 g/day) during the period between the biopsies. The patients whose liver fibrosis had deteriorated had a higher total alcohol consumption and higher drinking frequency between the biopsies. The degree of fibrosis progression was greater in patients with a total alcohol intake and drinking frequency above the median level for the group. A multiple logistic regression analysis showed that drinking frequency and time between biopsies were independently associated with fibrosis progression. Hence, even moderate alcohol intake seems to increase fibrosis progression in HCV-infected patients. From that point of view, total abstention ought to be recommended. If this is not achieved, occasional use of alcohol is probably less harmful than daily drinking for patients with low or moderate alcohol consumption.

Hepatitis B virus genotypes in Mongols and Australian Aborigines

Hepatitis B virus (HBV) is spread worldwide. Seven genotypes, A-G, have been described, differing by more than 8% of the genome. In eastern Asia and Oceania genotypes B and C are predominant. However, little is known about genotypes in Mongolia and Australian aborigines. We analysed the preS and S regions of HBV from 9 Mongols and 5 Australian Aborigines. All Mongolian strains were of genotype D and were most similar to Central Asian sequences. All the Australian strains were genetically of serotype ayw3, and could not be reliably classified by the S region analysis, but placed on a separate branch. By preS analysis, they were however clearly of genotype C. The 6-7% nucleotide difference from published Asian genotype C sequences suggests that they diverged from Asian genotype C branch more than 1000 years ago.

Phylogenetic origin of hepatitis B virus strains with precore C-1858 variant

Mutations that prevent the expression of the hepatitis B e antigen frequently emerge in the immunoreactive phase of infection. The predominant mutation, the precore G-->A-1896 mutation, is restricted by the variability at position 1858 and is rare in strains with cytosine at nucleotide 1858. The C-1858 variant is characteristic of genotype A. It also occurs in genotypes C and F, but not in B, D, or E, explaining the geographical variation in the prevalence of precore mutants. C-1858 strains have been frequently observed in southeast Asia, but have not been phylogenetically characterized. By sequencing eight complete hepatitis B virus genomes, C-1858 variants of east Asian origin were found to constitute a phylogenetic entity within genotype C that probably diverged several hundred years ago. Further study of the distribution of this variant is warranted.

Virological response to interferon therapy of chronic hepatitis B as measured by a highly sensitive assay

In the interferon (IFN) treatment of chronic hepatitis B, there is no accepted definition of virological response as measured by highly sensitive HBV DNA assays. In the present study of 98 patients given IFN (10 MU/day for 1 week, then 10 MU TIW for 11 weeks) with or without prednisolone priming, a virological response was identified as log HBV DNA/mL below 6.0 (by Amplicor Monitor, Roche) 6 months post-treatment. At this time, 92% (33/36) of the sustained responders (SR) still had detectable viraemia with log HBV DNA/mL at 4.30 +/- 0.15 (+/- SEM), as compared with 8.69 +/- 0.097 in nonsustained responders. Pretreatment viraemia below a threshold at 500 million copies/mL was associated with higher chance of response (P=0.023). Prednisolone enhanced the sustained response (53% vs. 30%, P=0.025), and in particular end-of-treatment response (ETR, 50% vs. 10%, P < 0.0001). ETR was predictive for SR (P < 0.0001), especially when log HBV DNA/mL was < 4.0 (PPV=92%). The potential value of differentiating the therapy of chronic hepatitis B on the basis of viraemia levels, as measured by highly sensitive assays, should be further investigated.

Monitoring virological responses to interferon-ribavirin and interferon monotherapy of chronic hepatitis C re-treated due to relapse or non-response

Adding the nucleoside analog ribavirin (RBV) to interferon (IFN) for treatment of HCV has improved the sustained response rates, but the mechanism by which RBV mediates viral clearance is not fully understood. In this study, a highly sensitive method (Codes Amplicor HCV Monitor) was used to monitor the early (first 12 weeks of therapy) and long-term virological response in 20 patients who were treated first with IFN and later, due to non-sustained response, with IFN-RBV. All 10 IFN relapsers displayed a prompt virological response at week 4 to both IFN and IFN-RBV therapy; nine of them showed a sustained response to IFN-RBV. Out of 10 IFN non-responders, five showed a sustained response to IFN-RBV. Four of these were HCV RNA-negative at week 4 of IFN-RBV therapy and two of them had a transient early virological response (RNA-negative at weeks 4-8) to IFN alone. Overall, of the 14 patients (nine IFN relapsers, five IFN non-responders) with a sustained response to IFN-RBV, 11 and 13 had HCV RNA below 2000 copies/ml at week 4 of IFN and IFN-RBV, respectively, as compared with one and one of six patients without a sustained response to IFN-RBV (p < 0.02). Thus, addition of RBV to IFN increased both viral clearance during the first 12 weeks of therapy and the rate of sustained response. Loss of viremia at week 4 of IFN was associated with a sustained response to IFN-RBV and was seen in 11 of 13 patients (85%) with genotypes 2 or 3, as compared with one of seven patients (14%) with genotype 1 (p = 0.0044).

Stent-graft repair of a splenic artery aneurysm

We present a case of splenic artery aneurysm (SAA) treated with stent-grafts. This new method offers the benefit of preserving the blood flow through the splenic artery. This in turn allows for subsequent sequential embolization of the spleen when indicated, as in our patient with hypersplenism. This is the first reported case of stent-graft repair of SAA.

Aneurysm expansion and retroperitoneal hematoma after thrombolysis for stent-graft limb occlusion caused by distal endograft migration

PURPOSE

To describe a complication of thrombolytic therapy used to treat graft limb occlusion precipitated by distal migration and kinking of an abdominal aortic stent-graft.

CASE REPORT

A 5.5-cm abdominal aortic aneurysm (AAA) in a 66-year-old woman was treated with Vanguard bifurcated stent-graft. At the 1-year follow-up, she complained of left leg claudication. Computed tomography (CT) showed a 36% reduction in maximum AAA diameter, but the stent-graft had migrated distally approximately 5 mm, and the left graft limb was occluded. Thrombolysis was initiated, but after approximately 8 hours, abdominal pain began. Emergent CT scanning revealed rapid aneurysm expansion and a retroperitoneal hematoma. Thrombolytic treatment was stopped; transfusions and thrombogenic drugs were given to restore hemodynamic stability. The aneurysm began to decrease in size. The occluded graft limb had been reopened by the lytic therapy, uncovering a stenosis in the native artery distal to the graft limb. Stent placement restored outflow. The retroperitoneal hematoma resolved over time, and the aneurysm sac shrank to its prelytic diameter. The patient is well with a functioning endograft 18 months after the occlusion (30 months after stent-grafting).

CONCLUSIONS

Caution must be taken when using thrombolysis in patients with endovascular aortic grafts because unexpected bleeding complications might arise. Thrombectomy, femorofemoral bypass, or stent or stent-graft extensions might be safer alternatives for treating occluded stent-graft limbs.

Levels of viraemia in subjects with serological markers of past or chronic hepatitis B virus infection

Subjects with serological markers for a past HBV infection may still have HBV DNA in their serum, but the levels of viraemia in such cases are not known. In the present study, of 63 consecutive HBsAg-negative, anti-HBc-positive serum samples with or without anti-HBs, 20 were HBV DNA-positive as analysed by a highly sensitive quantitative PCR, the Cobas Amplicor HBV Monitor test. However, all of these 20 samples had viraemia levels below 1000 copies/ml, compared with median viraemia levels of 10(8.6) and 10(4.3) copies/ml, respectively, in 98 HBeAg-positive and 124 HBeAg-negative HBsAg carriers. There was no difference in viraemia between subjects with anti-HBc alone compared with both anti-HBs and anti-HBc, nor between those with or without hepatitis C virus antibodies. The findings indicate that HBsAg-negative subjects may retain a low infectivity. Their risk for progressive liver damage is probably low, but this deserves further study.

Hepatitis B virus DNA levels, precore mutations, genotypes and histological activity in chronic hepatitis B

The present study aimed to clarify how viraemia levels reflect the clinical stages of chronic hepatitis B virus (HBV) infection, in particular studying whether 'healthy carriers' can be identified by analysing HBV DNA levels with a highly sensitive quantitative assay. Histology activity index (HAI), alanine aminotransferase (ALT) level, genotype and precore mutations were compared with the HBV DNA level, as measured using the Amplicor HBV Monitor assay in a prospective study. In 124 hepatitis B e antigen-negative (HBeAg-) patients, the majority with mild liver disease, log HBV DNA levels showed a Gaussian distribution around a geometric mean of 33 000 genome copies ml-1, and increasing HBV DNA level was associated with significantly higher inflammation (HAIinfl) and fibrosis (HAIfibr) scores and higher ALTi (ALT / the upper reference value). Severe inflammation (HAIinfl > or = 7) was seen in 83% (five of six), 36% (eight of 22) and 3% (one of 37) of HBeAg- patients with HBV DNA > 107, > 2 x 105 and < 104 copies ml-1, respectively. In severe HBeAg- hepatitis, patients with precore wild-type infection had lower HBV DNA levels than those with precore mutants. In 36 HBeAg-positive (HBeAg+) patients, no correlation between HBV DNA level and liver damage was seen. Ninety-six per cent of HBeAg- patients with ALTi < 0.5 had HAIinfl < or = 3. In HBeAg- carriers with ALTi 0.5-1.0, the relative risk for severe inflammation, comparing HBV DNA > 2 x 105 copies ml-1 vs < 2 x 105 copies ml-1, was 14.7. In conclusion, in HBeAg- carriers, HBV DNA < 104 copies ml-1 or ALTi < 0.5 indicates mild inflammation, while > 2 x 105 copies ml-1 of HBV DNA may justify further investigations. Precore status may be relevant for the interpretation of viraemia.

Acute hepatitis B in Western Sweden--genotypes and transmission routes

A retrospective study of acute hepatitis B (AHB) during 1995-1996 in Göteborg, Sweden, was carried out to investigate whether the increasing number of hepatitis B virus (HBV) carriers due to immigration in northwestern Europe has influenced the incidence or genotype heterogenicity. 24 cases of AHB were identified, the probable transmission route of which was intravenous drug use (IVDU) in 11 (46%), heterosexual in six (25%), homosexual in one, hemodialysis in two and unknown in four cases. In no case was the source an immigrant with chronic HBV infection. Genotype D was seen in 12 patients, seven being anti-HCV-positive IVD users, two probably infected heterosexually and three with an unknown source. Genotype A was found in six patients: three IVD users, a sexual partner of an IVD user and two dialysis patients. Genotype B was found in one patient infected during travel to Vietnam, and genotype C in one patient, probably infected sexually from a previously identified chronic carrier. In conclusion, genotype D is the main genotype and IVDU still the major risk factor for AHB in Goteborg, while transmission from immigrants appears to be of minor importance despite the fact that this group comprises over 90% of the young, highly infectious carriers.

Primary stenting in infrarenal aortic occlusive disease

PURPOSE

To evaluate the results of primary stenting in aortic occlusive disease.

METHODS

Thirty patients underwent primary stenting of focal concentric (n = 2) and complex aortic stenoses (n = 19), and aortic or aorto-iliac occlusions (n = 9). Sixteen patients underwent endovascular outflow procedures, three of whom also had distal open surgical reconstructions. Median follow-up was 16 months (range 1-60 months).

RESULTS

Guidewire crossing of two aorto-biiliac occlusions failed, resulting in a 93% (28/30) technical success. Major complications included one access hematoma, one myocardial infarction, one death (recurrent thromboembolism) in a patient with widespread malignancy, and one fatal hemorrhage during thrombolysis of distal emboli from a recanalized occluded iliac artery. One patient did not improve his symptoms, resulting in a 1-month clinical success of 83% (25/30). Following restenting the 26 stented survivors changed their clinical limb status to +3 (n = 17) and +2 (n = 9). During follow-up one symptomatic aortic restenosis occurred and was successfully restented.

CONCLUSIONS

Primary stenting of complex aortic stenoses and short occlusions is an attractive alternative to conventional surgery. Larger studies with longer follow-up and stratification of lesion morphology are warranted to define its role relative to balloon angioplasty. Stenting of aorto-biiliac occlusions is feasible but its role relative to bypass grafting remains to be defined.

Long-term mutation rates in the hepatitis B virus genome

Mutations in the hepatitis B virus (HBV) genome have so far been investigated in cross-sectional or short-term longitudinal studies. Information about long-term changes is lacking due to the difficulty of sampling over long observation periods. In this study, a retrospective approach was used that allowed the analysis of changes in the viral genome from transmission to late stages of infection without the requirement for sampling early during this period. The entire viral genome was sequenced from serum samples of three mothers and their 10 adult children, who presumably had been infected vertically. The emergence of mutations between birth and sampling (mean 26.5 years) was assessed by comparing the individual sequences with the sequence of the strain assumed to have been transmitted. The mean differences from this sequence were 0.02 and 0. 28% in seven asymptomatic and one symptomatic hepatitis B e antigen (HBeAg)-positive carriers, respectively, and 0.62 % in five HBeAg-negative carriers. Mutations occurred throughout the genome and 88% of the mutations caused amino acid substitutions spread over all genes. In HBeAg-negative carriers, the number of nucleotide and amino acid changes was independent of the severity of liver disease and, except the (1762)AGG(1764)-->TGA changes, no specific mutation was associated with liver disease. In conclusion, by using a novel method it was found that the entire HBV genome is extremely stable over long periods of time during the HBeAg-positive phase if the immune response (inflammation) is weak, whereas an average of 20 mutations emerged after development of hepatitis and/or loss of HBeAg without association with clinical outcome.

Endovascular repair of descending thoracic aortic aneurysms: an early experience with intermediate-term follow-up

PURPOSE

The purpose of this study was to report an initial experience with the endovascular repair of descending thoracic aortic aneurysm. Complications and intermediate-term morphologic changes were identified with the intent of altering patient selection and device design.

METHODS

Endografts were placed into 25 patients at high-risk for conventional surgical repair over a 3(1/2)-year period. Devices were customized on the basis of preoperative imaging information. Follow-up computed tomography scans were obtained at 1, 3, 6, and 12 months and yearly thereafter. Additional interventions occurred in the setting of endoleaks, migration, and aneurysm growth.

RESULTS

The overall 30-day mortality rate was 20% (12.5% for elective cases; 33% for emergent cases). There were 3 conversions to open repair. Neurologic deficits developed in 3 patients; 1 insult resulted in permanent paraplegia. Neurologic deficits were associated with longer endografts (P =.019). Three endoleaks required treatment, and 1 fatal rupture of the thoracic aneurysm treated occurred 6 months after the initial repair. Migrations were detected in 4 patients. The maximal aneurysm size decreased yearly by 9.15% (P =.01) or by 13.5% (P =.0005) if patients with endoleaks (n = 3 patients) were excluded. Both the proximal and distal neck dilated slightly over the course of follow-up (P =.019 and P =.001, respectively). The length of the proximal neck was a significant predictor of the risk for endoleakage (P =.02).

CONCLUSION

The treatment of descending thoracic aortic aneurysms with an endovascular approach is feasible and may, in some patients, offer the best means of therapy. Early complications were primarily related to device design and patient selection. All aneurysms without endoleaks decreased in size after treatment. Late complications were associated with changing aneurysm morphologic features and device migration. The morphologic changes remain somewhat unpredictable; however, alterations in device design may result in improved fixation and more durable aneurysm exclusion.