Using data from studies of health-related quality of life to describe clinical issues Examples from a longitudinal study of patients with advanced stages of cervical cancer

The focus of the paper is to describe how to present data from studies on health-related quality of life (H-QoL) in a way that is simple and clinically relevant. Data from a longitudinal study of patients with advanced stages of cervix cancer are used. One hundred and eighteen patients filled out questionnaires (including EORTC QLQ-C30) 7 times over a period of 2 years. The following issues are considered: (1) The use of a panel for an initial overview of data. (2) The visual difference between using mean and median values. (3) Box-whisker plots to illustrate the variability of the data. (4) The effect of combining categorical data into fewer categories. (5) Individual patient profiles showing the wide variability among patients. (6) A table showing the change of scores over a one-year period. (7) “Prognostic plots” dividing the initial scores and the following scores. (8) Plotting changes over time. (9) Illustration of the impact of non-random drop-out. (10) The effect of drop-out for the patients who fill out two sequential assessments. (11) The use of healthy controls to help answer the question “what is normal?”.     

Inhibition of 3-Hydroxy-3-Methylglutaryl–Coenzyme A Reductase and Application of Statins as a Novel Effective Therapeutic Approach against Acanthamoeba Infections

Acanthamoeba is an opportunistic pathogen in humans, whose infections most commonly manifest as Acanthamoeba keratitis or, more rarely, granulomatous amoebic encephalitis. Although there are many therapeutic options for the treatment of Acanthamoeba, they are generally lengthy and/or have limited efficacy. Therefore, there is a requirement for the identification, validation, and development of novel therapeutic targets against these pathogens. Recently, RNA interference (RNAi) has been widely used for these validation purposes and has proven to be a powerful tool for Acanthamoeba therapeutics. Ergosterol is one of the major sterols in the membrane of Acanthamoeba. 3-Hydroxy-3-methylglutaryl–coenzyme A (HMG-CoA) reductase is an enzyme that catalyzes the conversion of HMG-CoA to mevalonate, one of the precursors for the production of cholesterol in humans and ergosterol in plants, fungi, and protozoa. Statins are compounds which inhibit this enzyme and so are promising as chemotherapeutics. In order to validate whether this enzyme could be an interesting therapeutic target in Acanthamoeba, small interfering RNAs (siRNAs) against HMG-CoA were developed and used to evaluate the effects induced by the inhibition of Acanthamoeba HMG-CoA. It was found that HMG-CoA is a potential drug target in these pathogenic free-living amoebae, and various statins were evaluated in vitro against three clinical strains of Acanthamoeba by using a colorimetric assay, showing important activities against the tested strains. We conclude that the targeting of HMG-CoA and Acanthamoeba treatment using statins is a novel powerful treatment option against Acanthamoeba species in human disease.     

Anti-tissue factor pathway inhibitor activity in patients with primary antiphospholipid syndrome

The association between antiphospholipid antibodies and an increased risk of thrombosis in antiphospholipid syndrome (aPS) patients is probably caused by numerous mechanisms, including the effects of antibodies to phospholipid-binding proteins such as beta(2)-glycoprotein I and prothrombin. In this study, we investigated the inhibition of tissue factor pathway inhibitor (TFPI) in 33 patients with primary antiphospholipid syndrome (PAPS). TFPI was measured in PAPS patients using an amidolytic assay, dependent on the generation of activated factor X (Fxa), and this was compared with 55 healthy subjects. Functional levels of TFPI (mean +/- SD) were significantly lower in PAPS patients (0.89 +/- 0.37 U/ml) than the control group (1.05 +/- 0.15 U/ml) (P = 0.02). The difference was caused by a subset of five patients who had TFPI levels below the lower 99% confidence interval of the normal reference range, representing increased FXa generation in the assay system. IgG fractions were isolated from these five patients and five control subjects, then incorporated into normal plasma to measure FXa generation in the TFPI assay system. FXa generation was increased when polyclonal rabbit anti-human TFPI IgG (P < 0.0001) or PAPS IgG (P = 0.0001) were added to normal plasma, demonstrating inhibition of TFPI. The apparent anti-TFPI activity demonstrated in the five subjects with PAPS in this study may represent a significant new mechanism for thrombosis in patients with aPS, as it implies that increased tissue factor FVIIa-mediated thrombin generation might occur.     

Pyrimethamine in the myeloproliferative disorders: a forgotten treatment?

Eight patients with myeloproliferative disorders, five with polycythaemia rubra vera (PRV) and three with essential thrombocythaemia (ET), have been treated with the anti-folate drug Pyrimethamine for periods ranging from 1 to 24 years. In PRV this treatment was comparable in efficacy to that achieved with Busulphan or radioactive phosphorus, but required more frequent supervision. One patient was controlled on Pyrimethamine, having failed on conventional treatment. The major side effect was thrombocytopenia which was rapidly reversible on stopping the drug. In ET, Pyrimethamine produced satisfactory control of the platelet count and thrombocytopenia did not arise. No neurological sequelae were encountered. One patient developed a non-Hodgkin's lymphoma of the gut, but there were no other cases of secondary malignancy. Pyrimethamine may still have a role in the treatment of selected cases of myeloproliferative disorders.     

Traceability and calibration in temperature measurement: a clinical necessity

Patient temperature is a fundamental physiological measurement used primarily for observation and diagnosis, for example during surgery, intensive care, recuperation, or treatment. A variety of thermometers are used clinically and these can be separated into two categories, either contact (oral thermometers, rectal thermometers and temporal strips), or non-contact (ear thermometers, temporal thermometers and thermal imagers). To have the maximum confidence in the clinical performance of the temperature measurement instrument it is strongly desirable that the device be traceably calibrated to the International Temperature Scale of 1990 (ITS-90). Lack of traceable calibrations accredited to ISO17025 can lead to unreliability in temperature measurement and in some cases can have a deleterious effect on patient care. The National Physical Laboratory (NPL) maintains and disseminates the ITS-90 for contact and non-contact thermometry in the UK. The importance of accredited traceable calibrations and an outline of contact and non-contact thermometry standards are given here.     

Measuring thrombin generation based sensitivity to activated protein C using an automated coagulometer (ACL 9000)

Increased thrombin generation in the presence of activated protein C (APC) is known to be an independent risk factor for thrombosis. Although commercially available methods for measuring thrombin generation are available, none measure sensitivity to APC. We have developed an automated thrombin generation based APC sensitivity test, for use with defibrinated plasma using the automated coagulometer (ACL9000). A chromogenic substrate that is cleaved by thrombin at a slow rate, 7 pm tissue factor and 20 mum phospholipid (DOPC : DOPE : DOPS, 60 : 20 : 20) with and without 5 nm APC. Thrombin generation with [endogenous thrombin potential (ETP)(+APC)] and without APC (ETP), was expressed as a ratio relative to pooled normal plasma. Normal reference ranges were established in 30 normal subjects: ETP 0.73-1.06; ETP(+APC) 0.42-1.07. ETP(+APC) was found to be sensitive to factor V Leiden, oral contraceptive use, low levels of protein S and tissue factor pathway inhibitor and increased plasma factor VIII.     

Guide-lines for near patient testing: haematology

Summary These guide-lines provide a framework for the local arrangement of near patient testing (NPT) services for haematology tests. The guidance may be applied to medical and surgical units within hospitals (e.g. ITU, renal dialysis units, casualty) as well as general practitioners' surgeries, for blood counts and coagulation testing. The professional head of the central laboratory must take responsibility for all aspects of the NPT service, although there should be full discussion with the clinical departments involved and joint ownership of the results. NPT operators must be trained and accredited by the central laboratory. Equipment selected should normally have received a satisfactory evaluation report from the Medical Devices Agency (MDA), and should generate results that are comparable with those of the central laboratory. If a full MDA operation evaluation has not been performed, the purchaser should perform a local assessment according to the protocol in this document. The suitability of the equipment, imprecision, and comparability must be studied. The NPT equipment must be properly maintained and calibrated, and a record of patient identity, date and time of testing, reagent lot numbers, and operator must be kept. The central laboratory must participate in a suitable external quality assessment programme (EQA), and provide systems for EQA and internal quality control (IQC) of the NPT site.     

Complement and cytokine response in acute Thrombotic Thrombocytopenic Purpura

Complement dysregulation is key in the pathogenesis of atypical Haemolytic Uraemic Syndrome (aHUS), but no clear role for complement has been identified in Thrombotic Thrombocytopenic Purpura (TTP). We aimed to assess complement activation and cytokine response in acute antibody‐mediated TTP. Complement C3a and C5a and cytokines (interleukin (IL)‐2, IL‐4, IL‐6, IL‐10, tumour necrosis factor, interferon‐γ and IL‐17a) were measured in 20 acute TTP patients and 49 remission cases. Anti‐ADAMTS13 immunoglobulin G (IgG) subtypes were measured in acute patients in order to study the association with complement activation. In acute TTP, median C3a and C5a were significantly elevated compared to remission, C3a 63·9 ng/ml vs. 38·2 ng/ml (P < 0·001) and C5a 16·4 ng/ml vs. 9·29 ng/ml (P < 0·001), respectively. Median IL‐6 and IL‐10 levels were significantly higher in the acute vs. remission groups, IL‐6: 8 pg/ml vs. 2 pg/ml (P = 0·003), IL‐10: 6 pg/ml vs. 2 pg/ml (P < 0·001). C3a levels correlated with both anti‐ADAMTS13 IgG (r_s = 0·604, P = 0·017) and IL‐10 (r_s = 0·692, P = 0·006). No anti‐ADAMTS13 IgG subtype was associated with higher complement activation, but patients with the highest C3a levels had 3 or 4 IgG subtypes present. These results suggest complement anaphylatoxin levels are higher in acute TTP cases than in remission, and the complement response seen acutely may relate to anti‐ADAMTS13 IgG antibody and IL‐10 levels.