Heterogeneity after harmonisation: A retrospective cohort study of bleeding and stroke risk after the introduction of direct oral anticoagulants in four Western European countries

PURPOSE

Database heterogeneity can impact effect estimates. Harmonisation provided by common protocols and common data models (CDMs) can increase the validity of pharmacoepidemiologic research. In a case study measuring the changes in the safety and effectiveness of stroke prevention therapy after the introduction of direct oral anticoagulants (DOACs), we performed an international comparison.

METHODS

Using data from Stockholm, Denmark, Scotland and Norway, harmonised with a common protocol and CDM, two calendar-based cohorts were created: 2012 and 2017. Patients with a diagnosis code of atrial fibrillation 5 years preceding the 1-year cohort window were included. DOAC, vitamin K antagonist and aspirin treatment were assessed in the 6 months prior to the start of each year while strokes and bleeds were assessed during the year. A Poisson regression generated incidence rate ratios (IRRs) to compare outcomes from 2017 to 2012 adjusted for changes in individual-level baseline characteristics.

RESULTS

In 280 359 patients in the 2012 cohort and 356 779 in the 2017 cohort, treatment with OACs increased on average from 45% to 65%, while treatment with aspirin decreased from 30% to 10%. In all countries except Scotland, there were decreases in the risk of stroke and no changes in bleeding risk, after adjustment for changes in baseline characteristics. In Scotland, major bleeding (IRR 1.09, 95% confidence interval [CI] [1.00; 1.18]) and intracranial haemorrhage (IRR 1.31, 95% CI [1.13; 1.52]) increased from 2012 to 2017.

CONCLUSIONS

Stroke prevention therapy improved from 2012 to 2017 with a corresponding reduction in stroke risk without increasing the risk of bleeding in all countries, except Scotland. The heterogeneity that remains after methodological harmonisation can be informative of the underlying population and database.

Trends in psychiatric diagnoses, medications and psychological therapies in a large Swedish region: a population-based study

BACKGROUND

Health services utilization for mental health disorders is reported to increase sharply in many countries. The aim of this study was to report trends in all aspects of mental health care utilization in a total population sample.

METHODS

Repeated cross-sectional register study of the Stockholm Region (VAL) including both primary and secondary care. Trends in the proportion of adults in the total population of Stockholm Region with a recorded ICD-10 psychiatric diagnosis or psychological therapy during 2007-2017 as well as claims of psychiatric medication from 2011 were calculated.

RESULTS

The proportion of adults utilizing any mental health care increased from 13.2% in 2011 to 16.1% in 2017. In 2017, 49.3% were treated in primary care, 32.2% in secondary care and 18.5% were jointly managed. The increase was most pronounced in younger adults. Women were more likely to receive mental health care than men in all ages. Medication decreased from 71.0 to 67.7%, while psychological therapy increased from 33.1 to 37.6%. The use of psychiatric medication increased with age while psychological therapy decreased. All time trends were statistically significant (p < .0001).

CONCLUSION

Care for mental health disorders has been increasing mainly in primary care and was delivered to one in seven adult individuals in 2017. Interventions are needed to address the growing burden of mental health disorders while avoiding overtreatment.

3053High mortality in atrial fibrillation patients suffering ischemic stroke, intracranial hemorrhage or a gastrointestinal bleed and associations with the preceding antithrombotic treatment

Background

Anticoagulation treatment reduces the risk of stroke but increases the risk of bleeding in atrial fibrillation (AF) patients. There is little data on survival after a stroke or a severe bleed.

Objective

To analyze 90-day mortality in AF patients after an ischemic stroke, an intracranial hemorrhage (ICH) or a gastrointestinal bleed (GIB) and assess associations with the type of antithrombotic treatment preceding the event.

Methods

From the Stockholm Healthcare database (n=2.3 million inhabitants) we selected all AF patients suffering from an ischemic stroke, an intracranial bleed, or a severe GIB requiring acute hospital care between July 2011 and August 2018 and assessed 90-day mortality rates. We assessed current use of warfarin, non-vitamin K oral anticoagulants (NOAC), or antiplatelet agents at the time of the event. We used a Cox regression to calculate adjusted hazard ratios (aHRs), adjusting for components of the Charlson Comorbidity Index, the CHADsVASc score, the HAS-BLED score, comedication, and year of inclusion, for the association between treatment preceding the event and mortality. In addition, we performed log-rank tests in propensity score matched cohorts.

Results

Of 105 313 patients with AF, 6 017 were included after an ischemic stroke, 3 006 after an ICH, and 4 291 after a GIB. 90-day mortality rates were 25.1%, 31.6% and 16.2%, respectively. Patients suffering from an ischemic stroke were the oldest at 81.6±9.8 (S.D:) years of age followed by patients suffering from an ICH (80.2±9.8 years) or a GIB (78.7±10.5 years). A large proportion of patients suffering ischemic stroke (72%) had no anticoagulant treatment preceding the event. After ICH, there was a significantly increased risk of mortality in warfarin compared to NOAC treated patients after adjusting for confounders (aHR: 1.36 CI: 1.04–1.78). Patients receiving antiplatelets or no treatment had significantly higher mortality rates than patients on NOAC treatment, both after an ischemic stroke and a GIB, but there was no significant difference between warfarin and NOACs (aHR 0.84 CI: 0.63–1.12 after ischemic stroke, aHR 0.91 CI: 0.66–1.25 after GIB). Propensity score matched analyses yielded similar results.

Survival curves after event

Conclusion

Mortality rates are high in AF patients suffering from an ischemic stroke, an ICH, or a GIB. NOAC treatment was associated with a lower 90-day mortality after ICH than warfarin, but no such difference was found after ischemic stroke or GIB. After ischemic stroke and GIB, mortality rates were higher in antiplatelet treated and untreated patients compared to NOAC treated patients.

Acknowledgement/Funding

Swedish Heart Lung Foundation

P4745Concomitant oral anticoagulant and antidepressant therapy in patients with atrial fibrillation and risk of stroke and bleeding: a population based cohort study

Background

Anticoagulation treatment reduces the risk of stroke but increases the risk of bleeding in atrial fibrillation (AF) patients. Antidepressants use is associated with increased risk for stroke and bleeds.

Objective

To assess the association between antidepressant use in AF patients with oral anticoagulants and bleeding and stroke risk.

Methods

All AF patients newly prescribed with an oral anticoagulant in the Stockholm Healthcare database (n=2.3 million inhabitants) from July 2011 until 2016 were included and followed for one year or shorter if they stopped claiming oral anticoagulant treatment or had an outcome of interest. Outcomes were severe bleeds and strokes, requiring acute hospital care. During follow-up, patients were considered exposed to antidepressant after claiming a prescription for the duration of the prescription. With a time-varying Cox regression, we assessed the association between antidepressant use and strokes and bleeds, adjusting for confounders (i.e., age, sex, comorbidities, comedication, and year of inclusion). In addition, we performed a propensity score matched analysis to test the robustness of our findings.

Results

Of the 30,595 patients included after claiming a prescription for a NOAC (n=13,506) or warfarin (n=17,089), 4 303 claimed a prescription for an antidepressant during follow-up. A total of 712 severe bleeds and 551 strokes were recorded in the cohort. Concomitant oral anticoagulant and antidepressant use was associated with increased rates of severe bleeds (4.7 vs 2.7 per 100 person-years) compared to oral anticoagulant treatment without antidepressant use (aHR 1.42, 95% CI: 1.12–1.80), but not significantly associated with increased stroke rates (3.5 vs 2.1 per 100 person-years, aHR 1.23, 95% CI: 0.93–1.62). No significant differences were observed between different oral anticoagulant classes (i.e., warfarin or NOAC) or different antidepressant classes (i.e., SSRI, TCA, or other antidepressant). Additional propensity-score matched analyses yielded similar results but showed a significantly increased risk for stroke (HR: 1.47, 95% CI: 1.08–2.02).

Incidence rates of strokes and bleeds

Conclusion

Concomitant use of an oral anticoagulant and an antidepressant, irrespective of type, is associated with an increased bleeding risk. Increased awareness and a critical consideration for the need of an antidepressant is recommended in this population.

Acknowledgement/Funding

Swedish Heart Lung Foundation

Oral immunoglobulin treatment improved intestinal permeability in children with active Crohn's disease

AIM

Crohn's disease (CD) is a chronic mucosal inflammation that affects the intestinal barrier function, for example, by altering the intestinal permeability. This pilot clinical study investigated the impact of oral human immunoglobulin (OHIG) treatment on permeability characteristics in children with active luminal Crohn's disease.

METHODS

The study was performed at the Department of Paediatrics, Norrköping Hospital, Sweden. Intestinal permeability was studied in three boys aged 13, 15 and 18 years with active CD, before and after a six-week treatment programme with OHIG, using different-sized polyethylene glycols as the test molecules. Three age- and sex-matched children with active CD treated with exclusive enteral nutrition (EEN) were also studied.

RESULTS

OHIG and EEN resulted in virtually similar reductions in the signs and symptoms of mucosal inflammation. However, OHIG, unlike EEN, appeared to normalise mucosal transfer leading to a normalisation of the maximum permeation of the small PEG molecules, as well as less restrictions of the larger PEG molecules.

CONCLUSION

Our study found that OHIG appeared to normalise the mucosal barrier. This suggests that it could offer a new additional and versatile treatment for paediatric CD patients, with a minimal risk of adverse effects.

Urinary nitric oxide metabolites in children with celiac disease after long-term consumption of oats-containing gluten-free diet

OBJECTIVE

Oats are accepted in the gluten-free diet (GFD) for children with celiac disease (CD). Some reports have indicated, however, that not all celiac patients tolerate oats. We have previously shown that some children still have high levels of urinary nitric oxide (NO) metabolites as markers of intestinal inflammation after 1 year on GFD with oats. In this study, we measured urinary NO metabolites in CD children who had been consuming oats-containing GFD for an extended, 2-6-year period, also taking into consideration ordinary consumption of nitrite/nitrate-rich foods close to the urine sampling.

MATERIALS AND METHODS

Morning urinary nitrite/nitrate concentrations were measured in 188 pediatric CD patients. A questionnaire was used to elucidate factors possibly affecting the urinary levels, for example, dietary factors, asthma, or urinary tract infection.

RESULTS

Oats were consumed by 89.4% of the patients for a median time of 3 years. The median nitrite/nitrate level was 980 μM. The majority (70.2%) who consumed oats had low levels of urinary nitrite/nitrate, that is, <1400 μM, while 29.8% demonstrated high levels, that is, >1400 μM. Nitrite/nitrate-rich foods did not significantly influence the urinary concentrations.

CONCLUSION

The urinary levels of NO metabolites revealed two subpopulations, one with high and one with low levels. The high levels could be possibly due to poor adherence to the GFD, sensitivity to oats, or some unknown factor(s). Nitrate-rich foods, asthma, or urinary tract infection did not affect the result. The elevated levels of NO metabolites could indicate mucosal inflammation and pinpoint the need of careful follow-up of children on oats-containing GFD.

Effects of a food supplement rich in arginine in patients with smear positive pulmonary tuberculosis--a randomised trial

In tuberculosis (TB), the production of nitric oxide (NO) is confirmed but its importance in host defense is debated. Our aim was to investigate whether a food supplement rich in arginine could enhance clinical improvement in TB patients by increased NO production. Smear positive TB patients from Gondar, Ethiopia (n = 180) were randomized to a food supplementation rich in arginine (peanuts, equivalent to 1 g of arginine/day) or with a low arginine content (wheat crackers, locally called daboqolo) during four weeks. The primary outcome was cure rate according to the WHO classification and secondary outcomes were sputum smear conversion, weight gain, sedimentation rate, reduction of cough and chest X-ray improvement as well as levels of NO in urine (uNO) or exhaled air (eNO) at two months. There was no effect of the intervention on the primary outcome (OR 1.44, 95% CI: 0.69-3.0, p = 0.39) or secondary outcomes. In the subgroup analysis according to HIV status, peanut supplemented HIV+/TB patients showed increased cure rate (83.8% (31/37) vs 53.1% (17/32), p < 0.01). A low baseline eNO (<10 ppb) in HIV+/TB patients was associated with a decreased cure rate. We conclude that nutritional supplementation with a food supplement rich in arginine did not have any overall clinical effect. In the subgroup of HIV positive TB patients, it significantly increased the cure rate and as an additional finding in this subgroup, low initial levels of NO in exhaled air were associated with a poor clinical outcome but this needs to be confirmed in further studies.

Children with screening-detected coeliac disease show increased levels of nitric oxide products in urine

AIM

Increased concentration of nitric oxide (NO) metabolites, nitrite and nitrate, in the urine is a strong indication of ongoing small intestinal inflammation, which is a hallmark of the enteropathy of coeliac disease (CD). It has previously been shown that children with symptomatic, untreated CD have increased levels of NO oxidation products in their urine. The aim of this study was to investigate whether screening-detected, asymptomatic coeliac children display the same urinary nitrite/nitrate pattern.

METHODS

In a multicenter screening study, serum samples were collected from 7208 12-year-old children without previously diagnosed CD. Sera were analysed for anti-human tissue transglutaminase (tTG) of isotype IgA. Small bowel biopsy was performed in antibody-positive children, yielding 153 new cases of CD. In the screening-detected individuals, the sum of nitrite and nitrate concentrations in the urine was analysed and used as an indicator of NO production. For comparison, 73 children with untreated, symptomatic CD were studied.

RESULTS

The nitrite/nitrate levels in children with screening-detected CD and those with untreated symptomatic CD did not differ significantly. Both groups had significantly increased urinary nitrite/nitrate concentrations compared to the children with normal small bowel biopsy (p < 0.001).

CONCLUSION

  Children with screening-detected CD have increased production of NO just as children with untreated symptomatic CD. High NO metabolite levels in the urine may indicate a pathogenetic feature of CD and be a marker of major clinical importance.

Enhanced neutrophil expression of annexin-1 in coronary artery disease

The systemic inflammatory activity in patients with stable coronary artery disease (CAD) is associated with a dysregulated cortisol response. Moreover, an aberrant activation status of neutrophils in CAD has been discussed; and the question of glucocorticoid resistance has been raised. The anti-inflammatory actions of glucocorticoids are mediated by annexin-1 (ANXA1). We investigated the expression of glucocorticoid receptors (GR) and ANXA1, as well as the exogenous effects of ANXA1 on neutrophils in CAD patients and related the data to diurnal salivary cortisol. Salivary cortisol levels were measured in the morning and evening during 3 consecutive days in 30 CAD patients and 30 healthy individuals. The neutrophil expression of GR and ANXA1 was determined by flow cytometry. The effect of exogenous ANXA1 was determined in a neutrophil stimulation assay. The patients showed a flattened diurnal cortisol pattern compared with healthy subjects, involving higher levels in the evening. The neutrophil expression of GR-total and GR-alpha was decreased, whereas the GR-beta expression did not differ compared with controls. The neutrophil expression of ANXA1 was significantly increased in patients. Ex vivo, ANXA1 impaired the leukotriene B(4)-induced neutrophil production of reactive oxygen species in patients but not in controls. Our findings indicate a persistent overactivation of the hypothalamic-pituitary-adrenal axis in CAD patients but do not give any evidence for glucocorticoid resistance, as assessed by the neutrophil expression of GR and ANXA1. The altered neutrophil phenotype in CAD may thus represent a long-term response to disease-related activation.

Urinary nitric oxide excretion in infants with eczema

Eczema is characterized by inflammation of the skin and is commonly associated with food allergy. It has been suggested that nitric oxide (NO) is an important player in eczema, food allergy and intestinal inflammation. The aim of this study was to assess the levels of urinary NO breakdown products in infants with eczema and the effect of eczema treatment on NO levels. Ninety-four infants with eczema, 58 boys and 36 girls, with a mean age of 7.5 ± 5.2 months (mean ± s.d.) at inclusion were examined twice with an interval of 6 wk. The sum of nitrite and nitrate was measured colorimetrically in urinary samples from both visits and compared with clinical data concerning eczema severity, nutrition, gastrointestinal symptoms, asthma and skin prick positivity. The levels of NO products increased significantly from the first to the second visit: 289; 374 μm (median; IQR) vs. 457; 678 μm (median; IQR) (p < 0.001) in parallel with a significant improvement of the eczema. After eczema treatment consisting of skin care and elimination diet during the 6-wk interval between evaluations, the NO levels approached the values previously found in healthy children. The results support previous studies indicating that the homeostasis of nitrogen radicals is disturbed in childhood eczema.

Primary amyloidosis with increased plasma carcinoembryonic antigen concentration. A case report

A patient with suspected malignant disease had increased concentration of plasma carcinoembryonic antigen (CEA). Amyloidosis was demonstrated at autopsy. The amyloid fibril composition was characterized by immunohistochemical and immunochemical techniques and proved to be of the lambda light chain (AL) type. CEA was demonstrated in the liver parenchyma by using antihuman CEA antiserum. Increased plasma CEA concentration in a patient with primary amyloidosis has, to our knowledge, not been reported before.

Plasma atrial natriuretic peptide in cardiac transplant recipients. A prospective study

Cardiac transplantation in 10 patients with congestive heart failure resulted in reduction of high plasma concentrations of atrial natriuretic peptide (ANP), preoperatively five-fold above normal, to a level two-fold above normal, which was maintained throughout a 12-week follow-up period. Cardiac function was normalized in all patients. Transient increases in plasma ANP, in four cardiac recipients 3-10-fold their basal levels, could neither be related to rejection episodes nor to cardiac dysfunction, but rather to signs of fluid and sodium retention. High plasma ANP levels in cardiac transplant recipients suggest that the capacity to secrete ANP is preserved in the transplanted heart.

A long-term follow-up of patients with essential hypertension treated with captopril

Seventy-four patients from four short-term studies of captopril in mild-moderate essential hypertension continued in a cooperative long-term efficacy and tolerance program. The duration of observation is 2- greater than 4 years, the total treatment time being 2434 months. No development of resistance to therapy was observed. The total daily dose of captopril has been gradually decreased and in 20 patients changed from t.i.d. to b.i.d. regime. The drug has been well tolerated and only few and mild side-effects have been observed after the initial titration period. The drop-outs (n = 19) were mostly due to non-medical causes (n = 14). Except for one case of proteinuria, no laboratory abnormalities were detected and there were no signs of long-term toxicity.

Sustained antihypertensive effect of captopril combined with diuretics and beta-adrenergic blocking drugs in patients with resistant hypertension

Ten patients with severe hypertension and unsatisfactory blood pressure control during combined therapy with beta-adrenergic blocking drugs, diuretics, and vasodilators were treated with gradually increasing doses of captopril. Vasodilators were discontinued 24 hours prior to captopril administration. Six patients had essential, two renal, and two renovascular hypertension. Mild renal impairment was observed in four patients. Captopril effectively decreased blood pressure for 3 hours in all patients after the first dose. The antihypertensive effect appeared to be triphasic and was sustained in all but one patient during 12 months of observation. Captopril doses of 25-75 mg t.i.d. were sufficient to achieve acceptable blood pressure control (RR less than or equal to 160/100 mmHg) when given in the above mentioned combination. Side-effects were few and tolerable and discontinuation of captopril was not required.

Tuberculosis of the colon in a kidney transplant patient

A 58-year-old woman experienced recurrent fever episodes after kidney transplantation. She was treated with antibiotics because of suspicion of staphylococcus infection. Abdominal pain combined with haemorrhagic diarrhoea occurred eight months after transplantation. A barium enema revealed a stenotic process in the middle part of the ascending colon mimicking carcinoma, and hemicolectomy was consequently performed. Histological examination revealed tuberculosis with little granuloma formation and abundant acid-fast tubercle bacilli in the mucosa and submucosa, and only slight perigranulomatous reactions. The patient was successfully treated with triple antituberculous chemotherapy without deterioration of allograft function. Tuberculosis should be suspected in immunosuppressed patients suffering from pyrexia of unknown origin, even when chest X-ray is normal.

Nitric oxide production in the exhaled air of patients with pulmonary tuberculosis in relation to HIV co-infection

Background

Nitric oxide (NO) is essential for host defense in rodents, but the role of NO during tuberculosis (TB) in man remains controversial. However, earlier observations that arginine supplementation facilitates anti-TB treatment, supports the hypothesis that NO is important in the host defense against TB. Local production of NO measured in fractional exhaled air (FeNO) in TB patients with and without HIV co-infection has not been reported previously. Thus, our aim was to investigate levels of FeNO in relation to clinical symptoms and urinary NO metabolites (uNO).

Methods

In a cross sectional study, FeNO and uNO were measured and clinical symptoms, chest x-ray, together with serum levels of arginine, tumor necrosis factor alpha (TNF-alpha) and interleukin 12 (IL-12) were evaluated in sputum smear positive TB patients (HIV+/TB, n = 36, HIV-/TB, n = 59), their household contacts (n = 17) and blood donors (n = 46) from Gondar University Hospital, Ethiopia.

Results

The proportion of HIV-/TB patients with an increased FeNO level (> 25 ppb) was significantly higher as compared to HIV+/TB patients, but HIV+/TB patients had significantly higher uNO than HIV-/TB patients. HIV+ and HIV-/TB patients both had lower levels of FeNO compared to blood donors and household contacts. The highest levels of both uNO and FeNO were found in household contacts. Less advanced findings on chest x-ray, as well as higher sedimentation rate were observed in HIV+/TB patients as compared to HIV-/TB patients. However, no significant correlation was found between FeNO and uNO, chest x-ray grading, clinical symptoms, TNF-alpha, IL-12, arginine levels or sedimentation rate.

Conclusion

In both HIV negative and HIV co infected TB patients, low levels of exhaled NO compared to blood donors and household were observed. Future studies are needed to confirm whether low levels of exhaled NO could be a risk factor in acquiring TB and the relative importance of NO in human TB.

Intracellular oxidative activation in synovial fluid neutrophils from patients with rheumatoid arthritis but not from other arthritis patients

OBJECTIVE

To compare total and intracellular oxidative activation of blood and synovial fluid (SF) neutrophils from patients with rheumatoid arthritis (RA) and other arthritides with blood donor neutrophils.

METHODS

Peripheral blood and SF samples were obtained from 26 gonarthritis patients (13 RA, 13 non-RA) attending the rheumatology unit for therapeutic joint aspiration. Isolated neutrophils were stimulated by a formylated tripeptide (fMLF) or by microbeads coated with collagen-I. Formation of superoxide-anion-derived reactive oxygen species (ROS) was studied by luminol-enhanced chemiluminescence. Paired samples of blood and SF neutrophils from patients with active arthritis were compared with blood neutrophils from patients in remission and from 47 healthy blood donors.

RESULTS

SF neutrophils from patients with RA, but not from non-RA patients, showed high baseline intracellular ROS production. Blood neutrophils from arthritis patients in remission existed in a primed state as revealed by more rapid oxidative response after collagen-bead challenge and a more pronounced response after fMLF stimulation compared to healthy blood donors. Blood neutrophils from RA patients with ongoing gonarthritis, however, did not differ from healthy blood donors concerning oxidative activation, whereas blood neutrophils from non-RA patients with gonarthritis showed a significantly lower peak ROS production.

CONCLUSIONS

A novel finding with pathogenetic implications in our study is that SF neutrophils from patients with RA, but not other arthritides, are activated and produce ROS intracellularly. This implies that synovial neutrophils in RA are engaged in the processing of endocytosed material.

Urinary nitric oxide during one year of gluten-free diet with or without oats in children with coeliac disease

OBJECTIVE

Although in both adults and children with coeliac disease (CD) it is now recommended that oats be added to their gluten-free diet, there is still some controversy concerning the possible harmful effects of oats in some individuals. In this study concentrations of nitric oxide metabolites were repeatedly measured in the urine of children under investigation for CD, when on a gluten-free diet with or without oats.

MATERIAL AND METHODS

The study included 116 children, randomized to a standard gluten-free diet (GFD-std) or a gluten-free diet supplemented with wheat-free oat products (GFD-oats), over a one-year period. Small-bowel biopsy was performed at the beginning and end of the study. Morning urine samples were collected from 87 children and urinary nitrite/nitrate concentrations were monitored at 0, 3, 6, 9 and 12 months.

RESULTS

All patients were in clinical remission after the study period. There was a rapid decline in urinary nitrite/nitrate concentrations in both groups as early as after 3 months. No differences were seen between the study groups at any of the checkpoints. However, at the end of the study, the nitrite/nitrate values of 9 children in the GFD-oats group and 8 children in the GFD-std group had not normalized.

CONCLUSIONS

Children with CD on a gluten-free diet with oats display a similar reduction in urinary nitrite/nitrate as those on a traditional gluten-free diet. Some children, however, still demonstrate high nitrite/nitrate excretion after one year on either diet, indicating that long-term follow-up studies of children on an oats-containing diet are needed.

Helicobacter pylori SabA adhesin evokes a strong inflammatory response in human neutrophils which is down-regulated by the neutrophil-activating protein

The human pathogen Helicobacter pylori expresses two dominant adhesins; the Lewis b blood group antigen binding adhesin, BabA, and the sialic acid-binding adhesin, SabA. These adhesins recognize specific carbohydrate moieties of the gastric epithelium, i.e. the Lewis b antigen, Le(b), and the sialyl-Lewis x antigen, sLe(x), respectively, which promote infection and inflammatory processes in the gastroduodenal tract. To assess the contribution of each of BabA, SabA and the neutrophil activating protein (HP-NAP) in a local inflammation, we investigated the traits of H. pylori mutants in their capacity to interact with and stimulate human neutrophils. We thence found that the SabA adhesin was not only the key inducer of oxidative metabolism (Unemo et al. J Biol Chem 280:15390-15397, 2005), but also essential in phagocytosis induction, as evaluated by flow cytometry, fluorescence microscopy and luminol-enhanced chemiluminescence. The napA deletion resulted in enhanced generation of reactive oxygen species and impaired adherence to the host cells. In conclusion, the SabA adhesin stimulates human neutrophils through selectin-mimicry. Interestingly, HP-NAP modulates the oxidative burst, which could tune the impact of the H. pylori infection for establishment of balanced and chronic inflammation of the gastric mucosa.

Effects of CNI-1493 on human granulocyte functions

During acute bacterial infections such as sepsis and meningitis, activation of inflammatory mediators such as nitric oxide (NO) plays a crucial role in both pathogenesis and host defense. We have previously reported that CNI-1493, a macrophage deactivator, reduced mortality in infant rats infected with Haemophilus influenzae type b (Hib) with associated decrease in the number of granulocytes in the infected tissue. The aim of the present study was to investigate how CNI-1493 affects granulocytes and macrophages in vitro. Murine macrophages (RAW 264.7) pre-incubated with CNI-1493 prior to activation with lipopolysaccharide (LPS)/interferon gamma (IFNgamma) had decreased NO production measured as NO(2)(-)/NO(3)(-) levels and reduction in inducible NO-synthase (iNOS) expression. Reactive oxygen species (ROS) production was increased in formylmethionyl-leucyl-phenylalanine (FMLP)-stimulated granulocytes following CNI-1493 treatment, whereas F-actin content, motility and chemotaxis were decreased under the same conditions. The effects of CNI-1493 on both NO production in LPS/IFNgamma-activated macrophages and ROS production, F-actin content, motility and chemotaxis in granulocytes, may contribute to the reduced inflammatory response and increased survival in Hib-infected animals treated with CNI-1493.

De novo seropositive rheumatoid arthritis during immunosuppressive treatment after kidney transplantation

We detected de novo seropositive erosive rheumatoid arthritis (RA) in a patient seven years after successful cadaveric kidney transplantation (RTx). RA developed in spite of treatment with cyclosporine A (CyA), methylprednisolon (MP) and azathioprine (Aza), compounds often also used for treatment of active RA. Renal failure was due to diabetes mellitus (DM) nephropathy. Besides a slight increase in C-reactive protein (CRP) concentration two years after RTx, the clinical symptoms of RA were observed seven years after RTx. RA was confirmed by X-ray examination, isotopic skeletal scan and positive serum RA factor. After switching Aza to methotrexate (Mtx) treatment, his symptoms disappeared and CRP concentration returned to normal. Our patient had HLA DRB1 *0101, *0401 alleles and DQB1 *0501, *0302 alleles which have strong genetic association with both DM and RA. To our best knowledge, this is the first case in which de novo seropositive erosive RA developed while on treatment with triple immunosuppression after RTx. The immunosuppressive treatment probably masked the inflammation and symptoms of RA.

Inducible nitric oxide synthase (NOS II) is constitutive in human neutrophils

The objective was to study the expression of inducible nitric oxide synthase (NOS II) in and NO production by human blood neutrophils and in in vivo exudated neutrophils. Cellular expression of NOS II was evaluated by flow cytometry in whole blood, in isolated blood neutrophils, and in neutrophils obtained by exudation in vivo into skin chambers. Neutrophil NOS II was also demonstrated by Western blotting. Uptake of 3H-labelled L-arginine was studied in vitro and NOS activity measured in a whole cell assay by the conversion of 3H-arginine to 3H-citrulline. In contrast to unseparated blood cells, NOS II was demonstrable both in isolated blood neutrophils and exudated cells. The failure to detect NOS II by flow cytometry in whole blood cells thus proved to be due to the quenching effect of hemoglobin. Western blotting revealed a 130 kD band corresponding to NOS II in isolated blood neutrophils, but detection was dependent on diisopropylfluorophosphate for proteinase inhibition. L-arginine was taken up by neutrophils, but enzymatic activity could not be demonstrated. We conclude that human neutrophils constitutively express NOS II, but that its demonstration by FITC-labelling is inhibited by hemoglobin-mediated quenching in whole blood samples.

Inducible nitric oxide synthase is expressed in synovial fluid granulocytes

The objective of the study was to evaluate the NO-producing potential of synovial fluid (SF) cells. SF from 15 patients with arthritis was compared with blood from the same individuals and with blood from 10 healthy controls. Cellular expression of inducible nitric oxide synthase (iNOS) was analysed by flow cytometry. High-performance liquid chromatography was used to measure l-arginine and l-citrulline. Nitrite and nitrate were measured colourimetrically utilizing the Griess' reaction. Compared to whole blood granulocytes in patients with chronic arthritis, a prominent iNOS expression was observed in SF granulocytes (P < 0.001). A slight, but statistically significant, increase in iNOS expression was also recorded in lymphocytes and monocytes from SF. l-arginine was elevated in SF compared to serum (257 +/- 78 versus 176 +/- 65 micro mol/l, P = 0.008), whereas a slight increase in l-citrulline (33 +/- 11 versus 26 +/- 9 micro mol/l), did not reach statistical significance. Great variations but no significant differences were observed comparing serum and SF levels of nitrite and nitrate, respectively, although the sum of nitrite and nitrate tended to be elevated in SF (19.2 +/- 20.7 versus 8.6 +/- 6.5 micro mol/l, P = 0.054). Synovial fluid leucocytes, in particular granulocytes, express iNOS and may thus contribute to intra-articular NO production in arthritis.

Interstitial nephritis, acute renal failure in a patient with non-fulminant hepatitis A infection

This is the first report from Norway of a patient with interstitial nephritis and renal failure due to non-fulminant hepatitis A virus (HAV) infection. HAV infection was confirmed by positive anti-HAV IgM serology. All tests for other virus infections were negative. At admittance serum creatinine (s-Creat) and blood urea nitrogen (BUN) concentration were 539 microlmol/l and 32.6 mmol/l increasing the following days to 890 micromol/l and 39.9 mmol/l, respectively. Nine courses of hemodialysis had to be given. Kidney biopsy specimen showed interstitial edema, lymphocytic cell infiltration and acute tubular injury with normal glomeruli. Examination with immunohistochemistry was negative. In contrast to the findings associated with HBV and HCV infection in which glomerular disease is predominantly found, the HAV infection in our patient was associated with interstitial nephritis and acute tubular necrosis. The prognosis of the renal failure due to HAV infection was good although the recovery was substantially delayed.

Neutrophil leukocyte motility requires directed water influx

The ability of neutrophils to sense and move to sites of infection is essential for our defense against pathogens. For motility, lamellipodium extension and stabilization are prerequisites, but how cells form such membrane protrusions is still obscure. Using contrast-enhanced video microscopy and Transwell assays, we show that water-selective aquaporin channels regulate lamellipodium formation and neutrophil motility. Addition of anti-aquaporin-9 antibodies, HgCl(2), or tetraethyl ammonium inhibited the function(s) of the channels and blocked motility-related shape changes. On human neutrophils, aquaporin-9 preferentially localized to the cell edges, where N-formyl peptide receptors also accumulated, as assessed with fluorescence microscopy. To directly visualize water fluxes at cell edges, cells were loaded with high dilution-sensitive, self-quenching concentrations of fluorophore. In these cells, motile regions always displayed increased fluorescence compared with perinuclear regions. Our observations provide the first experimental support for motility models where water fluxes play a pivotal role in cell-volume increases accompanying membrane extensions.

The use of pretransplant erythropoietin to normalize hemoglobin levels has no deleterious effects on renal transplantation outcome

BACKGROUND

The aim of this study was to establish the outcome of renal transplantation in patients given pretransplant erythropoietin (EPO) treatment targeted at reaching a normal hemoglobin concentration (Hb), compared to those given EPO-treatment aimed at maintaining subnormal Hb.

METHODS

A total of 416 patients from Scandinavian countries and with renal anaemia were enrolled to examine the effects of increasing Hb from a subnormal level (90-120 g/liter) to a normal level (135-160 g/liter) by EPO treatment. Half of the patients were randomized to have their Hb increased, with the other half randomized to maintain a subnormal Hb. Thirty-two patients from the normal Hb group and 24 patients from the subnormal group received a renal graft during the study period. The outcomes of these transplantations were examined prospectively for 6 months.

RESULTS

Preoperative Hb levels were 143+/-17 and 121+/-14 g/liter in the two groups, respectively (P<0.0001). The Hb remained higher in the normal Hb group during the first 2 weeks after transplantation. The percentage of patients requiring postoperative blood transfusions in the normal Hb group was 16%, compared with 50% in the subnormal group (P<0.01). No statistically significant difference in the proportion of functioning grafts or in the serum creatinine levels could be detected. No correlation between EPO treatment and creatinine levels after transplantation was found. The frequency of adverse events was similar in the two groups.

CONCLUSIONS

EPO treatment aimed at reaching a normal Hb in renal transplant recipients reduces the postoperative requirement for blood transfusions and has no deleterious effects on kidney graft function.

[Water channels of the cell--aquaporins]

BACKGROUND

Several mechanisms in the body regulate the water transport within the cells up and down during physiological and pathological conditions. The discovery of aquaporins, water channel proteins, has brought more insight into and understanding of how water crosses plasma membranes within cells in body tissue.

MATERIAL AND METHODS

The functions of aquaporins are not fully understood; this paper summarise current knowledge of various aquaporins.

RESULTS

Known aquaporins are discussed in relation to some physiological, pathological and clinical conditions.

INTERPRETATION

In the future, measurements of aquaporin concentrations in urine and possibly in other samples will give us a broader picture of water exchange and a better understanding of the mechanisms underlying water production in clinical states like renal and heart failure and liver insufficiency. Moreover, by manipulating water channel proteins by compounds developed for this purpose, one may have a tool for treating some clinical disorders in which water depletion or water overload is an important factor.

Nitric oxide regulates the aggregation of stimulated human neutrophils

Neutrophil aggregation is mediated by both CD18 integrin and L-selectin. Nitric oxide attenuates the integrin-mediated adhesion of neutrophils to collagen and to endothelium and may therefore affect aggregation as well. FMLP-stimulated neutrophils exposed to l-arginine showed increased and prolonged aggregation, whereas cells pretreated with L-NAME did not differ from FMLP-stimulated controls. Nitric oxide is known to induce ADP ribosylation of G-actin, which inhibits polymerization. We detected equivalent levels of total F-actin in cells pretreated with l-arginine or L-NAME and non-pretreated controls. However, neutrophils pretreated with l-arginine and stimulated by CD18 integrin cross-linking exhibited a more limited increase in total F-actin, compared to control and L-NAME-pretreated cells. Thus at least two signaling pathways may be involved FMLP-stimulated aggregation, mediated by CD18 integrins. More specifically, it is plausible that FMLP-receptor signaling upregulates CD18 integrins and endogenous NO subsequently modulates CD18-mediated signaling to prolong aggregation, possibly through ADP-ribosylation of actin.

Nitric oxide-releasing particles inhibit phagocytosis in human neutrophils

We have constructed a yeast (Saccharomyces cerevisiae) particle capable of releasing NO, by loading heat-killed yeast particles with a hydrophobic NO-generating substance, GEA-5171. This particle decreased phagocytosis in solution, as measured with flow cytometry, to about 80% of control values. Phagocytosis on a surface, as counted under the microscope, was also decreased by about 20%. The nitric oxide furthermore counteracted the production of oxygen metabolites by neutrophils to about 20% of control values. The inhibitory effect was most pronounced for the intracellular production, as could be seen when neutrophils preincubated with NO-releasing particles were stimulated with chemotactic agent (FMLP) or phorbol ester (PMA). In conclusion, NO has inhibitory effects on both phagocytosis and the respiratory burst of neutrophils. Since nitric oxide is a hydrophobic gas and an air pollutant, there is a possibility that it accumulates in particles which then become more resistant to elimination.

Fosinopril versus enalapril in the treatment of hypertension: a double-blind study in 195 patients

The new angiotensin-converting enzyme (ACE) inhibitor fosinopril was compared with the ACE inhibitor enalapril in a multicenter (n = 11), multinational (Denmark, Finland, Iceland, Norway, and Sweden), double-blind, randomized, parallel-group 24-week study in 195 patients with mild to moderate essential hypertension [supine diastolic blood pressure, (SDBP) > or = 95 to < or = 110 mm Hg]. After discontinuing all previous antihypertensive medication, patients were entered into a placebo lead-in period of 4-6 weeks, followed by 24 weeks of randomized treatment with the active compounds administered with a double-dummy technique. The dose of fosinopril was 20 mg, which could be increased to 40 mg after 8 weeks (average 25.6 mg); that of enalapril was 10 mg, which could be increased to 20 mg after 8 weeks (average 12.9 mg). Hydrochlorothiazide 12.5 mg could be added after 16 weeks and was administered to 27% of the patients in the fosinopril group and to 30% in the enalapril group. All drugs were administered once daily. Supine systolic BP (SSBP) decreased from 157 to 143 mm Hg in the fosinopril group (p < 0.01), and from 159 to 147 mm Hg in the enalapril group (p < 0.01). SSDP decreased from 100 to 89 mm Hg in the fosinopril group (p < 0.01) and from 100 to 92 mm Hg in the enalapril group (p < 0.01). Throughout the study period, fosinopril reduced SSBP and SDBP numerically more than did enalapril, by 0-3 mm Hg. Adverse events (AE) caused withdrawal of study medication in 8 patients in the fosinopril group and in 14 patients in the enalapril group (NS). The number of reported AE was not statistically different in the two groups. Inhibition of the ACE was assessed in a subgroup of patients (n = 26, 13 in each group). Fosinopril caused a greater inhibition of ACE at the doses used in the present study, which was statistically significant. Both fosinopril and enalapril caused statistically significant reductions in BP of a similar magnitude, and both agents were well tolerated. However, fosinopril was consistently numerically slightly more effective than enalapril in reducing BP. There were fewer withdrawals due to AE (NS) in the fosinopril group, and the overall recorded AE were fewer in the fosinopril group (NS).

Nitric oxide regulates the chemiluminescence from stimulated human neutrophils

Nitric oxide produced from L-arginine by a variety of cells, is a biologically active compound that can react with iron and thiols. The objective of this study was to investigate the effects of nitric oxide on the respiratory burst from human neutrophils. Treatment with nitroprusside increased the chemiluminescence from neutrophils stimulated with PMA or collagen, but not from cells stimulated with FMLP. Addition of L-arginine increased the chemiluminescence after stimulation with any of the three stimuli, while N omega-nitro-L-arginine methyl ester decreased it. Low doses of nitric oxide, either endogenously or exogenously produced, probably inhibited catalase or glutathione, leading to an increase in hydrogen peroxide available for chemiluminescence detection. This indicates that nitric oxide may reduce the protection against hydrogen peroxide in tissue and in invading catalase-positive bacteria.

Angio-oedema induced by enalapril

We report the case of a patient who, 9 months after initiation of enalapril and hydrochlorothiazide combination treatment for hypertension, developed angio-oedema with near fatal outcome. Our patient was successfully intubated using a flexible bronchofiberoscope. This case demonstrates that patients given an angiotensin-converting enzyme (ACE) inhibitor may develop serious facial and laryngeal swelling even several months after the initiation of treatment. The occurrence of even mild swelling should lead to prompt cessation of the drug. Patients with incipient ACE inhibitor-related angio-oedema should, without any delay, be referred to hospital for emergency treatment.

Hypertension in cyclosporin A-treated patients is independent of circulating endothelin levels

OBJECTIVES

To measure blood pressure (BP), plasma endothelin-1 (ET-1), atrial natriuretic peptide (ANP), antidiuretic hormone (ADH) and aldosterone (ALDO) concentration, and plasma renin activity (PRA) in patients treated with a low-dose cyclosporin A (CyA).

DESIGN

An open study of patients with rheumatoid arthritis (RA) or palmoplantar pustulosis (PPP).

SETTING

Out-patient clinics at the Central Hospital of Jyväskylä and Helsinki University Central Hospital.

SUBJECTS

CyA was given to 25 patients with RA and to 10 patients with PPP.

INTERVENTION

RA patients were given CyA at a dose of 2.5 +/- 0.13 mg kg-1 body weight (BW) to 3.47 +/- 0.79 mg kg-1 BW (mean values +/- SD) at the start of the study and after 6 months, respectively, and the CyA dose was 2.67 +/- 0.13 mg kg-1 BW decreasing to 2.07 +/- 0.96 mg kg-1 (P < 0.001) after 4 months in PPP subjects.

RESULTS

Systolic (sBP) and diastolic blood pressure (dBP) increased from 127.8 +/- 13.6/79.7 +/- 8.4 mmHg to 140.0 +/- 19.8/83.8 +/- 9.7 mmHg during the study (P < 0.03). Plasma ET-1, ANP, ALDO and ADH concentration and PRA did not change during 4 to 6 months of CyA treatment. The plasma ANP concentration was constantly higher in CyA-treated RA patients (112 +/- 87 ng 1-1 to 118 +/- 78 ng 1-1) than in PPP patients (37.3 +/- 26 ng 1-1 to 47.7 +/- 39.9 ng 1-1; P < 0.02). The serum creatinine concentration remained within the normal range, but increased from baseline (76.7 +/- 11.9 mumol 1-1), to 90 +/- 15.4 mumol 1-1 (p < 0.001). The serum magnesium concentration decreased significantly (P < 0.005) after 6 months of CyA treatment in RA patients. No correlation was found between serum creatinine and plasma ET-1 concentration.

CONCLUSIONS

Increased blood pressure during CyA treatment was independent of circulating ET-1 levels. A low dose of CyA did not induce increased ET-1 synthesis as judged from plasma samples. The high plasma ANP level observed in RA patients could be due to fluid retention caused by concomitant treatment with non-steroid anti-inflammatory drugs. Fluid retention and decreased magnesium levels could also be involved in the development of hypertension in CyA-treated subjects.

Nitric oxide reduces hydrogen peroxide production from human polymorphonuclear neutrophils

Nitric oxide has been reported to affect both adhesion and respiratory burst of neutrophils. This indicates a possible role of nitric oxide in regulation of acute inflammatory responses. Release of oxygen metabolites from neutrophils can be measured using luminol-enhanced chemiluminescence and this method can detect both extracellularly and intracellularly released oxygen metabolites. Neutrophils treated with nitroprusside and activated with FMLP, type I collagen or PMA decreased their extracellular release of oxygen metabolites, while their intracellular release was almost unaffected. The effect of nitroprusside was mediated by nitric oxide since treatment with cyanide had the opposite effect. N-ethylmalemide treatment decreased both extra- and intracellular release of oxygen metabolites. This indicates that nitric oxide affects membrane-bound NADPH-oxidase either indirectly or directly, and not a cytosol factor of the oxidase as earlier shown for N-ethylmaleimide. In conclusion, extracellular nitric oxide attenuates extracellularly released oxygen metabolites from activated neutrophils in an inflammatory response.

Priming of oxidative response in human neutrophils by anti-CD18 monoclonal antibodies

Type I collagen, the most abundant protein in the body, after acid extraction adheres to and can induce a respiratory burst from neutrophils. It has been proposed that the effects of collagen are mediated via the CD18 subfamily of integrins. In the present study, adhesion was measured by affinity chromatography in a column containing collagen-coated microcarriers, while oxygen metabolite production was measured with luminol-dependent chemiluminescence. Neutrophil adherence to collagen was attenuated by anti-CD18 monoclonal antibodies. The respiratory burst in response to collagen was not affected by the antibodies. Incubation of neutrophils with anti-CD18 antibodies prior to stimulation with FMLP increased both the extra- and intracellular respiratory burst. Treatment with antibodies prior to PMA stimulation increased only the extracellular respiratory burst. In conclusion, the respiratory burst from neutrophils is primed by pretreatment with anti-CD18 monoclonal antibodies. The collagen-stimulated respiratory burst is probably also primed, but the effect is hidden by the simultaneous attenuation of adhesion.

S-nitroso-N-acetylpenicillamine reduces leukocyte adhesion to type I collagen

The initial step in the migration of neutrophils to the extravascular space is adhesion to the endothelium. We examined the effect of nitric oxide on this process by treating human neutrophils with S-nitroso-N-acetylpenicillamine (SNAP), a NO-producing compound. Since NO has been shown to increase the level of cGMP in other cell types, we used 8-Br-cGMP in order to mimic the effects of NO. Indeed, both these treatments resulted in a reduced adhesion of neutrophils to type I collagen coated surfaces. After a prolonged incubation with SNAP, the adhesion was the same as for untreated cells. SNAP incubation reduced the F-actin content in the cells whereas 8-Br-cGMP increased it, demonstrating different mechanisms of action on F-actin. These data suggest that endothelium-derived nitric oxide is an important endogenous modulator of neutrophil adhesion, but the effect is not mediated by a cGMP-dependent regulation of F-actin levels.

Raised plasma endothelin-1 concentration in patients with nephropathia epidemica

Nephropathia epidemica (NE) with renal syndrome, caused by the Puumala-virus, is manifested clinically by the triad of fever, hemorrhage and renal failure. We observed raised plasma concentrations of endothelin-1 (ET-1) and atrial natriuretic peptide (ANP) in 23 patients during the acute phase of NE. They all developed transient renal failure and all displayed characteristics of NE, also verified by a rapid IgG antibody test. Blood pressure was normal or low in all subjects during the acute phase of the disease. Plasma ET-1 and ANP levels returned to normal following recovery one month later. The cause of increased ET-1 synthesis in NE remains unknown. It may be related to vascular damage or extravasation of blood. ET-1 may participate in the pathogenesis of acute renal failure of NE. Raised plasma ANP levels were most likely caused by fluid retention during the acute phase of NE. However, high levels of circulating ET-1 might have contributed to increased release of ANP.

Increased plasma angiotensinogen in cardiac transplantation patients

OBJECTIVES

Interleukin 6 (IL-6) stimulates the production of angiotensinogen (renin substrate, RS), an acute phase reactant and the precursor of the potent vasoconstrictor angiotensin II. This study assesses the effect of cardiac transplantation on plasma levels of angiotensinogen and interleukin 6.

METHODS

Effects of cardiac transplantation on plasma levels of renin substrate and IL-6 were studied in twelve patients with NYHA IV end-stage heart failure. Renin substrate, IL-6, plasma renin activity, C-reactive protein and serum amyloid A were determined 1 day before cardiac transplantation, and 1 day, 1 week, 4 weeks and 12 weeks postoperatively. Renin substrate was measured by both direct and indirect radioimmunoassay. An indirect assay measures intact renin substrate only, capable of releasing angiotensin I, while a direct assay measures both intact renin substrate and des-angiotensin I-renin substrate, the residue of renin substrate after cleavage of angiotensin I.

RESULTS

Plasma renin substrate and IL-6 increased significantly on day 1 as compared with preoperative levels. Plasma renin substrate increased (measured by direct and indirect assay) by 64 and 50%, respectively, IL-6 levels by 43%. Plasma IL-6 returned to preoperative (normal) levels by 4-12 weeks. Plasma renin substrate levels remained elevated for the follow-up period of 12 weeks. The direct assay always gave higher values than the indirect assay, presumably due to consumption of renin substrate by renin. Consequently, a negative correlation between plasma renin activity and renin substrate measured with indirect assay was observed.

CONCLUSIONS

Our findings suggest that cardiac transplantation brings about an acute phase reaction, mediated partly by IL-6, with increased synthesis of acute phase proteins like renin substrate. This may result in increased angiotensin II levels. Considering the trophic effects of angiotensin II on vascular tissue, increased production of renin substrate may contribute to the development of proliferative cardiovascular changes in heart transplant recipients.

Ophthalmic manifestations of epidemic nephropathy

An ophthalmic examination was performed on 29 epidemic nephropathy patients consequently treated in the Central Hospital of Central Finland during the acute phase of the disease. Twenty-six of those patients were reexamined after an interval of one month. In the acute phase of the disease pathological ophthalmic changes were found in 15 cases (52%). The symptoms observed were conjunctival injection, oedema, flare and cell reaction in anterior chamber, anisochoria, retinal oedema, acute glaucoma and myopic shift of refraction. The main effect of disease on intraocular pressure was pressure-lowering. The myopic shifts were not dependent on initial refraction. In one case of acute glaucoma this shift could be explained by swelling and forward movement of the lens.

Complications of nephropathia epidemica: three cases

Haemorrhagic fever with renal syndrome (HFRS) in Scandinavia is called nephropathia epidemica (NE), and is caused by the Puumala-virus, which belongs to the Hanta-virus genus. The clinical course of NE is mostly benign, complications are uncommon, and deaths are rarely observed. We report the cases of three patients who developed serious complications in the course of NE caused by the Puumala-virus. One patient died within 24 h after admission, another developed progressive neuromuscular dysfunction (Guillain-Barré syndrome) which required auxiliary ventilation for several weeks before a slow recovery, and a third patient developed empty sella syndrome with pituitary gland insufficiency. In the first two cases the diagnosis of NE was confirmed by a rapid avidity assay for IgG antibody against Puumala-virus. In the third case the clinical course, and demonstration of NE immunity 16 years later, suggested that NE might have caused the hypopituitarism. Some patients with NE caused by the Puumala-virus may require intensive-care treatment, and the development of late complications such as empty sella syndrome and hypopituitarism should be taken into consideration.

[The endothelial cell as an endocrine organ--endothelin]

Endothelin is a newly discovered potent vasoconstrictive polypeptide released by endothelial cells in response to various stimuli, including vasoactive peptides such as angiotensin II, adrenaline and vasopressin, and thrombocyte products like transforming beta growth factor and thrombin. Endothelin is believed to exert its main effects locally, in a paracrine or autocrine way. In vascular tissue, endothelin induces longlasting contraction of smooth muscle cells, leading to decreased blood flow, especially in the coronary and renal circulation, together with an increase in systemic blood pressure. It acts also mitogenically in vascular smooth muscle cells. Endothelin stimulates release of aldosterone and catecholamines in non-vascular tissue, and inhibits release of renin. A physiological function of endothelin may be to modulate vascular tone, and increased levels of circulating endothelin are seen after the "cold pressor test". Moreover, plasma endothelin concentration is elevated during acute myocardial infarction, in acute renal failure, in patients with hypertension, and during cardiogenic chock. What role endothelin plays in the development of these conditions, and in other disorders such as vascular spasm and atherosclerosis is uncertain.

Hormonal changes in patients with severe chronic congestive heart failure treated by ultrafiltration

Plasma atrial natriuretic peptide (ANP), antidiuretic hormone (ADH), plasma renin activity (PRA), and circulatory haemodynamics were studied in five patients with chronic congestive heart failure undergoing ultrafiltration on two consecutive days. The patients were in the New York Heart Association class IV, and were considered candidates for heart transplantation. A mean of 3.3 +/- 0.5 litres of fluid was removed during each ultrafiltration. Plasma ANP concentration remained unchanged during ultrafiltration: 369 +/- 151 pg/ml at start and 316 +/- 116 pg/ml at the end, while plasma ADH concentration and PRA increased from 5.1 +/- 2.1 to 7.5 +/- 3.4 pg/ml (P less than 0.02), and 5.9 +/- 3.0 to 7.7 +/- 3.2 ng/ml (P less than 0.03) respectively (n = 10). After treatment, plasma ADH and PRA declined to baseline values within 1 h. Pulmonary artery, pulmonary capillary wedge, and right atrial pressures decreased significantly, while blood pressure and heart rate remained constant during ultrafiltration. A volume of 3.3 +/- 0.5 litres of fluid was removed, and caused an increase in colloid osmotic pressure from 22.0 +/- 3.0 to 33.7 +/- 3.9 mmHg (P less than 0.02). It was unexpected that plasma ANP concentration did not decline. Due to long-standing severe heart failure the atrial wall may have lost some of its elastic properties, resulting in less ability to adapt to reduced filling pressures. Accordingly, atrial wall stretch remained unchanged, explaining the constant ANP levels. Ultrafiltration treatment caused an increased responsiveness to diuretic therapy, and four patients survived long enough to receive heart transplants.