Clinical practice of hereditary angioedema in Belgium: opportunities for optimized care

INTRODUCTION

Hereditary angioedema (HAE) is a rare disorder characterized by unpredictable painful and potentially life-threatening swelling episodes. The international WAO/EAACI guideline on the diagnosis and management of HAE was recently updated and provides up-to-date guidance for the management of. In this paper, we assessed to what extent the Belgian clinical practice was aligned with the revised guideline, and whether there were opportunities to optimise Belgian clinical practice in HAE.

METHODS

We compared the updated international guideline for HAE with information we acquired on Belgian clinical practice, a Belgian patient registry and expert opinion analysis. The Belgian patient registry was developed with the involvement of eight Belgian reference centers for HAE patients. Eight Belgian experts, physicians in the participating centers, included patients in the patient registry and participated in the expert opinion analysis.

RESULTS

The main action points to further optimise the Belgian clinical practice of HAE are Work towards total disease control and normalize patients' life by considering the use of new and innovative long-term prophylactic treatment options; (2) inform C1-INH-HAE patients about new long-term prophylactic therapies; (3) assure the availability of on-demand therapy for all C1-INH-HAE patients; (4) implement a more universally used assessment including multiple aspects of the disease (e.g. quality of life assessment) in daily clinical practice; and (5) continue and expand an existing patient registry to assure continued data availability on C1-INH-HAE in Belgium.

CONCLUSIONS

In light of the updated WAO/EAACI guideline, five action points were identified and several other suggestions were made to optimise the Belgian clinical practice in C1-INH-HAE.

Hereditary angioedema (HAE) in Belgium: results from a national survey

Background

Hereditary angioedema (HAE) is a rare heritable disorder that is characterized by recurrent, circumscribed, nonpitting, nonpruritic, often painful subepithelial swellings of sudden unpredictable onset that generally fade during 48-72 h. Epidemiological data of hereditary angioedema patients in Belgium is lacking.

Methods

We set up a nation-wide, multicentric study involving the 8 Belgian hospitals known to follow-up patients with Type I and II HAE. All Belgium HAE patients were asked to fill out questionnaires that mainly covered demographic data, family history, and detailed information about diagnosis, treatment and burden of their Type I and II HAE.

Results

112 patients with type I or type II HAE could be included. Median delay between first symptoms and diagnosis was 7 years. 51% of patients had experienced pharyngeal or tongue swelling and 78% had experienced abdominal symptoms, both known to cause an important reduction in quality of life. 60% of symptomatic patients reported to receive long term prophylactic treatment. Human plasma-derived C1-esterase inhibitor concentrate was used by 56.3% of patients. 16.7% and 27.1% of patients used a 17-α-alkylated androgen and tranexamic acid as long term prophylactic therapy.

Conclusions

We present the first nation-wide epidemiological study regarding HAE in Belgium. Our data show that the morbidity of HAE is not to be underestimated. Knowledge and dissemination of this data is critical in raising awareness, encouraging development of therapies and optimising nationwide management.

[Apexxnar®, 20-valent pneumococcal conjugate vaccine]

Streptococcus pneumoniae infections cause bacteremic and non-bacteremic community-acquired pneumonia and invasive pneumococcal diseases (IPD) such as bacteremia, sepsis and acute meningitis. They are potentially lethal. Although polysaccharide vaccines (PPV23, Pneumovax 23®) have already provided protection in at-risk individuals, they have been imperfect, mainly because the development of anti-polysaccharide antibodies occurs without the help of T cells. The introduction of immunogenic protein conjugate vaccines (ICVs) has overcome this problem and provided better and longer lasting protection. The first available vaccine of this type for adults was Prevenar 13®, targeting 13 polysaccharides of S. pneumoniae (PCV13). A new vaccine, Apexxnar®, targeting 20 polysaccharides (PCV20), the 13 of Prevenar 13®, to which 7 other serotypes considered to be equally responsible for invasive infections have been added, has recently been launched. Clinical studies have demonstrated a good immunogenic response against all 20 serotypes in adult patients who are either vaccine-naive or previously vaccinated with PPV23 and/or PCV13. Furthermore, the tolerance of the PCV20 vaccine was found to be comparable to that of Prevenar 13®. Vaccination with PCV20 involves a single injection. The Belgian Superior Health Council has recently reiterated the importance of vaccinating at-risk individuals against S. pneumoniae (a vaccination that is still under-performed). It now recommends vaccination with PCV20 (Apexxnar®) as the preferred primary vaccination regimen in high-risk adults with co-morbidities or in good health aged between 65 and 85 years.

[Phage therapy, an additional strategy against multidrug-resistant bacteria]

Phages are viruses that infect bacteria in a very specific way. They are naturally present throughout the biosphere and are also involved in various biological processes in humans. The beginning of the twentieth century saw the birth of phage therapy which consisted of using phages to fight against bacterial infections. Very quickly, however, the medical community turned away in favour of antibiotics. In recent years, bacteria that are multi-resistant to antibiotics have appeared and are giving rise to renewed interest in phages in the face of this therapeutic impasse. This review aims to rediscover phage therapy in the medical profession, by detailing its mechanisms of action, its clinical aspects and its practical modalities of use in Belgium. Future challenges are also outlined.

[Monogenic autoinflammatory diseases. An introduction on a translational mode to]

Autoinflammatory diseases refer to a broad spectrum of diseases that are primarily due to an abnormality in the regulation of natural immunity. Some are polygenic and highly influenced by the environment, others are monogenic. This article is devoted to a family of monogenic autoinflammatory diseases that is very important because it includes the emblematic Mediterranean familial fever, the first autoinflammatory disease described as such and which heavily affects the Eastern Mediterranean populations. We will discuss the regulatory mechanisms of inflammasomes and the impact of certain mutations on their function. General principles of treatment and diagnosis will also be discussed. Other autoinflammatory diseases (including type 1 interferonopathies and NF-?b and TNF-? axis abnormalities) deserve to be discussed later on.

[Dual therapies as a treatment of human immunodeficiency virus : the end of a paradigm ?]

Current guidelines increasingly consider some dual antiretroviral therapies as bona fide alternatives to triple therapy as these regimens are proven to be safe and efficacious. These drug sparing regimens have many advantages such as a reduction of drug burden and subsequent toxicity, preservation of future treatment options, cost reduction and avoidance of drug-drug interactions. In the past, some dual therapies were associated with a higher risk of selecting resistance mutations. Nevertheless, current and future dual regimens based on powerful drugs with a high genetic barrier are non-inferior to triple therapies and could become the future gold standard for HIV treatment.

Could KL-6 levels in COVID-19 help to predict lung disease?

BACKGROUND

Coronavirus disease COVID-19 has become a public health emergency of international concern. Together with the quest for an effective treatment, the question of the post-infectious evolution of affected patients in healing process remains uncertain. Krebs von den Lungen 6 (KL-6) is a high molecular weight mucin-like glycoprotein produced by type II pneumocytes and bronchial epithelial cells. Its production is raised during epithelial lesions and cellular regeneration. In COVID-19 infection, KL-6 serum levels could therefore be of interest for diagnosis, prognosis and therapeutic response evaluation.

MATERIALS AND METHODS

Our study retrospectively compared KL-6 levels between a cohort of 83 COVID-19 infected patients and two other groups: healthy subjects (n = 70) on one hand, and a heterogenous group of patients suffering from interstitial lung diseases (n = 31; composed of 16 IPF, 4 sarcoidosis, 11 others) on the other hand. Demographical, clinical and laboratory indexes were collected. Our study aims to compare KL-6 levels between a COVID-19 population and healthy subjects or patients suffering from interstitial lung diseases (ILDs). Ultimately, we ought to determine whether KL-6 could be a marker of disease severity and bad prognosis.

RESULTS

Our results showed that serum KL-6 levels in COVID-19 patients were increased compared to healthy subjects, but to a lesser extent than in patients suffering from ILD. Increased levels of KL-6 in COVID-19 patients were associated with a more severe lung disease.

DISCUSSION AND CONCLUSION

Our results suggest that KL-6 could be a good biomarker to assess ILD severity in COVID-19 infection. Concerning the therapeutic response prediction, more studies are necessary.

[Pharmacological therapies against COVID-19 : state of the art, between hopes and disappointments]

The COVID-19 outbreak has raised numerous attempts of diverse pharmacological interventions to improve the prognosis of the infection, especially among hospitalized patients due to an acute respiratory distress syndrome (ARDS). Initially, these interventions used known medications capable to directly target SARS-CoV-2 by investigating several antiviral therapies already applied with some success in other viral infections. Among them remdesivir appears to be the most promising drug against SARS-CoV-2. Then, owing to the deleterious impact of the cytokine storm, medications that more specifically inhibit proinflammatory cytokines (especially interleukin-1 and interleukin-6) were tested. Hydroxychloroquine, sometines combined with azithromycin, has benefited for a while from a media buzz. However, hopes initially founded in all such drugs turned into disappointments because the specificities of SARS-CoV-2 make this virus resistant to most pharmacological interventions. Only glucocorticoids, dexamethasone and hydrocortisone, were associated with a significant reduction in mortality of patients with ARDS due to COVID-19, most probably via non-specific anti-inflammatory effects. These corticosteroids are currently recommended by the World Health Organisation. An intensive research is ongoing worldwide to find effective combined therapies or innovative drugs which could unequivocally improve the prognosis of COVID-19 at the different stages of the infection.

[Hurdles to HIV cure. Part 2 : ongoing HIV replication despite therapy]

The antiretroviral therapy (ART) has proven its effectiveness in improving the life expectancy of people infected with human immunodeficiency virus (HIV). Based on the inhibition of HIV replication, ART ensures the reduction of plasma viral load to undetectable levels on long-term. Unfortunately, once ART is interrupted, the viral load rises up. Consequently, the therapy remains not curative. The reasons for this failure lie in the presence of latent reservoirs of the virus and/or the presence of ongoing replication, responsible for the persistence of the virus. This ongoing replication despite ongoing therapy has been demonstrated in sanctuary sites where the penetration of antiretroviral drugs is suboptimal. Moreover, some treatment intensification studies, mostly through addition of an integrase inhibitor, transiently resulted in increases in HIV replication by-products, highlighting that such strategies could reduce ongoing replication. Although the debate is still open, confirming the presence of this ongoing replication and finding strategies to eliminate it would be part of the key to a cure for HIV.

[Hurdles to HIV cure. Part 1 : the latent reservoirs]

The human immunodeficiency virus (HIV), responsible for acquired immunodeficiency syndrome or AIDS, is a major public health problem. In Belgium, 2 to 3 new cases are diagnosed every day. Since the advent of combined antiretroviral treatments in 1996, the life expectancy and quality of life of infected patients have greatly improved. However, to date there is no cure for HIV. Individuals infected with HIV must remain on antiretroviral treatment for life. One of the reasons for the difficulty in finding a cure for HIV is that the virus can remain in a latent form, i.e. dormant, in some of the cells it infects. These latent reservoirs are not recognized by the immune system and can reactivate and thus restart the infection if the patient stops the treatment. These latent reservoirs are therefore a major obstacle to cure HIV and a great deal of research is being conducted by the scientific community to find an eradication strategy. In this article, we will present the different characteristics of these latent reservoirs and the different strategies put in place to identify and eliminate them.

[Schnitzler syndrome]

This is the case report of a 57-year-old women with a 10-year long history of urticarial-like exanthema and monoclonal immunoglobulin M Kappa gammopathy, associated to arthralgia with pain of the lower limbs. A cutaneous biopsy and an inflammatory syndrome on laboratory testing helped to diagnose an urticarial vasculitis. A treatment with colchicine was set up but the response to therapy was not satisfactory. The diagnosis of Schnitzler syndrome was eventually suggested based on the combination of monoclonal gammopathy, urticarial and pain. A therapy with anakinra, an interleukin-1-receptor antagonist (IL-1), was started accordingly. The response was remarkable on skin rash, bone pain and laboratory testing including inflammatory syndrome.

[Therapeutic progress in the control of uncomplicated Plasmodium falciparum malaria]

Malaria is a worldwide public health problem. In Europe, data show an increasing trend of imported cases in the last ten years. Following an alarming observation reporting resistance to anti-malarial drugs, new effective treatments have been developed in early 21st century. These are artemisinin and its derivatives. Artemisinin-based combination therapies (ACT) are now recommended by the World Health Organisation (WHO) since 2006 as the first-line treatment for uncomplicated Plasmodium falciparum malaria. However, resistance phenomena to these new drugs have been described in South-East Asia since 2009. It is thus necessary to use them properly and to monitor their use to preserve their effectiveness in the future.

Week 48 Resistance Analyses of the Once-Daily, Single-Tablet Regimen Darunavir/Cobicistat/Emtricitabine/Tenofovir Alafenamide (D/C/F/TAF) in Adults Living with HIV-1 from the Phase III Randomized AMBER and EMERALD Trials

Darunavir/cobicistat/emtricitabine/tenofovir alafenamide (D/C/F/TAF) 800/150/200/10 mg is being investigated in two Phase III trials, AMBER (NCT02431247; treatment-naive adults) and EMERALD (NCT02269917; treatment-experienced, virologically suppressed adults). Week 48 AMBER and EMERALD resistance analyses are presented. Postbaseline samples for genotyping/phenotyping were analyzed from protocol-defined virologic failures (PDVFs) with viral load (VL) ≥400 copies/mL at failure/later time points. Post hoc analyses were deep sequencing in AMBER, and HIV-1 proviral DNA from baseline samples (VL <50 copies/mL) in EMERALD. Through week 48 across both studies, no darunavir, primary PI, or tenofovir resistance-associated mutations (RAMs) were observed in HIV-1 viruses of 1,125 participants receiving D/C/F/TAF or 629 receiving boosted darunavir plus emtricitabine/tenofovir-disoproxil-fumarate. In AMBER, the nucleos(t)ide analog reverse transcriptase inhibitor (N(t)RTI) RAM M184I/V was identified in HIV-1 of one participant during D/C/F/TAF treatment. M184V was detected pretreatment as a minority variant (9%). In EMERALD, in participants with prior VF and genoarchive data (N = 140; 98 D/C/F/TAF and 42 control), 4% had viruses with darunavir RAMs, 38% with emtricitabine RAMs, mainly at position 184 (41% not fully susceptible to emtricitabine), 4% with tenofovir RAMs, and 21% ≥ 3 thymidine analog-associated mutations (24% not fully susceptible to tenofovir) detected at screening. All achieved VL <50 copies/mL at week 48 or prior discontinuation. D/C/F/TAF has a high genetic barrier to resistance; no darunavir, primary PI, or tenofovir RAMs were observed through 48 weeks in AMBER and EMERALD. Only one postbaseline M184I/V RAM was observed in HIV-1 of an AMBER participant. In EMERALD, baseline archived RAMs to darunavir, emtricitabine, and tenofovir in participants with prior VF did not preclude virologic response.

A retrospective analysis omalizumab treatment patterns in patients with chronic spontaneous urticaria: a real-world study in Belgium

Background

Chronic spontaneous urticaria (CSU) is characterized by the repeated occurrence of persistent hives and/or angioedema for ≥6 weeks, without specific external stimuli. H₁‐antihistamines have long been the standard of care of CSU, but many patients remain uncontrolled even at 4× the approved dose. Add‐on therapy with omalizumab has proven effective in clinical trials, but little is known about omalizumab treatment in Belgium.

Objective

To collect real‐world clinical data on omalizumab treatment in adults with CSU in Belgium.

Methods

This was an observational, retrospective chart review of adults with CSU, who initiated omalizumab treatment between August 2014 and December 2016 (maximum 28 months follow‐up).

Results

In total, 235 patients were included (median time from symptom onset to diagnosis, 5.4 months; median time from diagnosis to commencing omalizumab, 6.7 months). Treatments used before/after commencing omalizumab did not always adhere to guidelines; many patients (26.4%/11.1%) received first‐generation H₁‐antihistamines, while 20.4% used omalizumab monotherapy after initiating treatment. The mean interval between omalizumab administrations was 4.8 (SD 1.7) weeks; 67.8% of patients had ≥1 interval prolongation and/or shortening. Mean baseline 7‐day Urticaria Activity Score (UAS7) was 32.0 (SD 6.05); this improved to 12.6 (SD 11.2) after 1 month of omalizumab. About 67.2% of patients reached UAS7 ≤ 6 (well controlled) during the study. A total of 87 patients stopped omalizumab and never restarted before the end of the observation period; the most prevalent reason was remission of symptoms (49.4% of patients), followed by lack of effect (12.6%), lost to follow‐up (6.9%) and adverse events (3.4%). Headache was the most common adverse event (n = 8/82). No anaphylaxis was reported.

Conclusions

This study revealed that patients initiated on omalizumab in Belgium had severe CSU at baseline, and showed substantial improvements after 1 month of treatment. Greater adherence to the prescription of guideline‐recommended medications is needed for the treatment of CSU.

[Emergency department utilization by HIV-positive adults in a Belgian setting]

The use of the emergency department (ED) by human immunodeficiency virus (HIV)-infected adults undergoes an evolution following the introduction of antiretroviral therapy (ART). Improving our knowledge about ED use characteristics will contribute to a correct diagnosis and therapeutic approach in this patient group, at the moment they are discharged from the ED. We conducted a one-year retrospective study on characteristics of ED use involving 1026 patients living with HIV. The majority of them was treated with antiretroviral therapy (95 %) and had a viral load lower than 50 copies (73.6 %). Among them, 117 patients (11.8 %) were admitted at least once to the ED. The most common ED discharge diagnoses were related to trauma (30 %). This study shows that the great majority of diagnoses were not related to infectious diseases (6.3 %, of which half were HIV-related). One hypothesis to explain these results would be that HIV-positive adults in this study had excellent antiretroviral coverage and were well controlled in terms of HIV.

A case of giant cell arteritis associated with culture-proven Coxiella burnetii aortitis

A case of proven Coxiella burnetii aortitis, possibly associated with giant cell arteritis (GCA), is reported. A 72-year-old man, who is a hunter, presented with weight loss, fever, jaw claudication, and hardened temporal arteries associated with a persistent inflammatory syndrome and arteritis of the whole aorta, including the brachiocephalic arteries, as seen on ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography. The diagnosis of GCA was retained, and treatment with prednisolone was started. Given the aneurysm of the abdominal aorta, the patient underwent replacement of the abdominal aorta with an allograft. Histology showed intense chronic arteritis attributed to atherosclerosis with dissection. However, Coxiella burnetii infection was confirmed by serology and then by culture and molecular biology on the surgical specimen. A combination of hydroxychloroquine and doxycycline was added to tapered prednisolone and the outcome was favourable.

[Endocarditis of mitral and aortic prosthetic heart valves caused by Aggregatibacter aphrophilus]

We present the case of an acute endocarditis of mitral and aortic prosthetic heart valves caused by Aggregatibacter aphrophilus (Haemophilus aphrophilus-paraphrophilus). This third report in the literature emphasizes the diagnostic work-up and the role of positron emission tomography combined with computed tomography in this setting. The specificities of endocarditis due to the HACEK group (Haemophilus spp., Aggregatibacter, Cardiobacterium hominis, Eikenella corrodens and Kingella spp.) and the specific microbiological data and therapeutic options pertinent to this germ are discussed.

[HIV cure : a realistic perspective ?]

More than 30 years after its discovery, human immunodeficiency virus (HIV) continues to be a major global public health issue. Antiretroviral therapy increases survival and quality of life of HIV-infected patients but is not curative. Indeed, interruption of therapy invariably leads to the re-emergence of detectable viral replication, since HIV persists in extremely long-lived viral latent reservoirs. Those viral latent reservoirs constitute the major source of viral recovery following antiretroviral treatment interruption and are considered as the most important hurdle to HIV eradication. Multiple strategies aimed at targeting the HIV latent reservoirs are intensively being explored. We discuss here the most recent innovative works that will hopefully contribute to find a cure for HIV.

[Obesity, high blood pressure, hypercholesterolaemia, and untreated diabetes in HIV-infected and HIV-uninfected Adults in Mbuji-Mayi (Democratic republic of congo)]

Little is known about the major cardiovascular risk factors in HIV-infected as compared to the HIV-uninfected patients in the Democratic Republic of Congo (DR Congo). We determined the prevalence of hypertension, obesity (BMI ≥ 30 kg/m²), total cholesterol > 200 mg/dl, HDLcholesterol &≤ 40 mg/dl, and glycemia > 126 mg/dl. We also calculated the average and/or median of total cholesterol, HDL-cholesterol, and glycemia among HIV-infected and HIV-uninfected patients.We conducted a cross-sectional study that enrolled 592 HIV-uninfected and 445 HIV-infected patients of whom 425 (95.5%) were on first-line antiretroviral therapy based on stavudine-lamivudine-nevirapine. Clinical and laboratory data of the patients were collected. The results were analyzed by chi-square, t-student, and Wilcoxon rank sum tests. 11.5% of HIV-infected patients had an average blood pressure suggesting hypertension versus 10.6% of HIV-uninfected (P = 0.751). But in absolute value, HIVinfected patients had a median of diastolic blood pressure of 90 mmHg versus 85 mmHg of HIV-uninfected (P < 0.001). 4.04% of HIV-infected patients had a BMI suggesting obesity versus 6.08% of HIV-uninfected patients (P = 0.187). For fasting glucose: 2.50% of HIV-infected patients versus 4.20% of HIV-uninfected patients had a serum fasting glucose suggesting diabetes (P<0.176). 11.9% of HIV-infected patients had a total cholesterol greater than 200 mg/dl versus 7.4% of HIVuninfected patients (P=0.019). For HDL-cholesterol: 36.40% of HIV-infected patients had a serum fasting ≤ 40 mg/dl versus 15.70% of HIV-uninfected patients (P < 0.001). HIV-infected patients had a median fasting total cholesterol higher (140 mg/ dl) thanHIV-uninfected patients (133mg/dl) [P=0.015].HIVuninfected patients had a median fasting HDL-cholesterol higher (58.5 mg/dl) than HIV-infected patients (49 mg/dl) [P < 0.001]. HIV-infected women were more likely to have a higher mean of total cholesterol: 147.70 #x00B1; 52.09 mg/dl versus 135.72 &#x00B1; 48.23 mg/dl for the HIV-infected men (P = 0.014) and of HDL-cholesterol: 55.80 ± 30.77 mg/dl versus 48.24 ± 28.57mg/dl for the HIV-infected men (P = 0.008). In this study population, prevalence of hypertension was elevated in HIVinfected versus HIV-uninfected patients. Being HIV positive on first-line antiretroviral therapy based on stavudine-lamivudine-nevirapine was associated with high prevalence of total cholesterol > 200 mg/dl and HDL-cholesterol ≤ 40 mg/dl. Proactive screening and prompt management of dyslipidemia and hypertension in this population should be a priority.

[Miliary tuberculosis in a patient under adalimumab]

We describe a case of atypical miliary tuberculosis diagnosed by molecular testing in a patient suffering from psoriasis arthritis treated by adalimumab. Tuberculosis may have a non-classical presentation in patients under biological treatments. We briefly discuss the difficulties underlying the diagnosis and treatment of tuberculosis, especially in patients suffering from fever of unknown origin.

[PREVENAR 13®, A PNEUMOCOCCAL CONJUGATE VACCINE FOR THE PREVENTION OF PNEUMOCOCCAL INFECTONS IN ADULTS AT RISK]

Pneumococcal infections remain a major public health issue in aging people. The recent publication of the CAPITA trial evaluating the efficacy of 13-valent pneumococcal conjugate vaccine (PCV13, Prevenar 13®) in elderly subjects has brought several countries including Belgium to modify their vaccinal recommendations. These new developments have motivated us to write this brief review about the burden of pneumococcal disease, the mechanism of action of conjugate vaccines, the clinical efficacy of PCV13 with a special emphasis on CAPITA data. The questions of herd protection and serotype substitution are also introduced as well as a summary of the more recent guidelines.

Transmission of HIV Drug Resistance and the Predicted Effect on Current First-line Regimens in Europe

Transmitted human immunodeficiency virus drug resistance in Europe is stable at around 8%. The impact of baseline mutation patterns on susceptibility to antiretroviral drugs should be addressed using clinical guidelines. The impact on baseline susceptibility is largest for nonnucleoside reverse transcriptase inhibitors.

Background. Numerous studies have shown that baseline drug resistance patterns may influence the outcome of antiretroviral therapy. Therefore, guidelines recommend drug resistance testing to guide the choice of initial regimen. In addition to optimizing individual patient management, these baseline resistance data enable transmitted drug resistance (TDR) to be surveyed for public health purposes. The SPREAD program systematically collects data to gain insight into TDR occurring in Europe since 2001.

Methods. Demographic, clinical, and virological data from 4140 antiretroviral-naive human immunodeficiency virus (HIV)–infected individuals from 26 countries who were newly diagnosed between 2008 and 2010 were analyzed. Evidence of TDR was defined using the WHO list for surveillance of drug resistance mutations. Prevalence of TDR was assessed over time by comparing the results to SPREAD data from 2002 to 2007. Baseline susceptibility to antiretroviral drugs was predicted using the Stanford HIVdb program version 7.0.

Results. The overall prevalence of TDR did not change significantly over time and was 8.3% (95% confidence interval, 7.2%–9.5%) in 2008–2010. The most frequent indicators of TDR were nucleoside reverse transcriptase inhibitor (NRTI) mutations (4.5%), followed by nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations (2.9%) and protease inhibitor mutations (2.0%). Baseline mutations were most predictive of reduced susceptibility to initial NNRTI-based regimens: 4.5% and 6.5% of patient isolates were predicted to have resistance to regimens containing efavirenz or rilpivirine, respectively, independent of current NRTI backbones.

Conclusions. Although TDR was highest for NRTIs, the impact of baseline drug resistance patterns on susceptibility was largest for NNRTIs. The prevalence of TDR assessed by epidemiological surveys does not clearly indicate to what degree susceptibility to different drug classes is affected.

Late presentation to HIV testing is overestimated when based on the consensus definition

Objectives

In 2011, a consensus was reached defining “late presenters” (LPs) as individuals presenting for care with a CD4 count < 350 cells/μL or with an AIDS‐defining event, regardless of CD4 count. However, a transient low CD4 count is not uncommon in recent infections. The objective of this study was to investigate how measurements of late presentation change if the clinical stage at the time of diagnosis is taken into account.

Methods

Case surveillance data for newly diagnosed patients in Belgium in 1998–2012 were analysed, including CD4 count at diagnosis, the presence of AIDS‐defining events, and recent infections (< 6 months) as reported by clinicians in the case of acute illness or a recent negative test. First, proportions of LPs were calculated according to the consensus definition. Secondly, LPs were reclassified as “nonlate” if infections were reported as recent.

Results

A total of 7949 HIV diagnoses were included in the study. Recent infections were increasingly reported over time, accounting for 8.2% of new infections in 1998 and 37.5% in 2012. The consideration of clinical stage significantly modified the proportion of LPs: 18.2% of men who have sex with men (MSM) diagnosed in 2012 would be classified as LPs instead of 30.9% using the consensus definition (P < 0.001). The proportion of patients misclassified as LPs increased significantly over time: 5% in MSM in 1998 vs. 41% in 2012.

Conclusions

This study suggests that low CD4 counts in recent infections may lead to overestimation of late presentation when applying the consensus definition. The impact of transient CD4 count on late presentation estimates should be assessed and, if relevant, the introduction of clinical stage in the definition of late presentation should be considered.

[Diagnosis and treatment of hereditary angioedema: clinical illustration and brief literature review]

Hereditary angio-oedema is an autosomal dominant transmitted disease that is characterized by swellings of the subcutaneous or mucosal tissues. The edematous manifestations develop over a few hours and disappear spontaneously in a few days. This disease, which is due to an excess of bradykinine, a peptide that induces vasodilatation and increases vascular permeability, is different from angioedema mediated by histamine (frequently accompanied by urticaria). This difference explains the inefficiency of antiallergic therapies to treat the crises. This condition, although rare, is important to know because it is potentially lethal if the edema leads to laryngeal obstruction. After the report of a clinical example, this paper will consider the pathophysiology and the classification of angio-oedema without urticaria. New therapeutic recommendations for the treatment of hereditary angio-oedema will also be considered.

Pneumococcal vaccination: what have we learnt so far and what can we expect in the future?

Individuals <2 years and ≥50 years of age, as well as those with other specific risk factors, are especially vulnerable to invasive pneumococcal disease (IPD). Conjugate vaccines have been developed against encapsulated bacteria such as Streptococcus pneumoniae to provide improved immune responses. The 7-valent pneumococcal conjugate vaccine (PCV7) has significantly reduced the burden of vaccine-type pneumococcal diseases in children, including invasive disease and pneumonia and acute otitis media. There have also been significant declines in antimicrobial resistance in 7-valent vaccine serotypes and carriage of S. pneumoniae in the post-PCV7 era. Two to three years after the introduction of PCV13, there is emerging, global evidence of a reduced burden of pneumococcal diseases in children, including declines in IPD (UK and Germany) and nasopharyngeal carriage of PCV13 serotypes (Portugal and France). The functional immunogenicity of PCV13 in individuals ≥50 years of age has been demonstrated in clinical trials in comparison with the 23-valent pneumococcal polysaccharide vaccine and for children and adults 6 to 49 years of age. Between 2011 and 2013, PCV13 received market authorisation by the European Medicines Agency (EMA) for these additional age groups and is now available in Europe for the prevention of pneumococcal disease in all age groups.

[Aging and cancer: coincidence or etiologic relationship?]

In Belgium and in other countries, the Cancer Registry data show an increased incidence of cancers related to age, the majority of tumors being diagnosed beyond 60 years. However, the mechanisms responsible for this increase are not clear. Cancer could be chronologically associated with aging because of the long latency period between the exposition to carcinogenic agents and the appearance of clinical signs. Aging could also predispose directly to cancer by different mechanisms (impaired immune response, increased oxidative stress, shortening of telomeres, accumulation of senescent cells). In this review, we propose to describe different hypotheses which could explain the increased incidence of cancers in the elderly.

[Hooping cough in adults, think about it!]

We report the case of a 47 year old patient who had been suffering from persistent cough for more than three weeks. Patient coughed predominantly during night time, without fever. The amoxicillin-clavulanic acid initially prescribed was not effective. A series of complementary investigations were performed before serology finally identified Bordetella pertussis infection after two months of symptoms which improved slowly without evident benefit of macrolide treatment. The diagnosis of whooping cough was also established for the wife of the patient with fast resolution of the symptoms after rapid unset of treatment with macrolides.

[Role of vitamin D in HIV infection]

Besides its role in bone metabolism, vitamin D shows properties on autoimmune, oncological, cardiovascular, metabolic, or infectious diseases. In this article, we talk about interpellant relationships between vitamin D and HIV. This hormone plays an important role in HIV infection, as much at a skeletal level than in the course of the disease itself. First, we notice that a low vitamin D status is currently associated with HIV infection. Moreover, it is now known that low rate of 1,25-dihydroxyvitamin D in HIV patients is associated with advanced clinical HIV infection and increased mortality. Thus, vitamin D deficiency has to be considered as an important factor in HIV progression. Indeed, vitamin D increases macrophage activity, in some way through autophagy, and this process can inhibit HIV-1 infection. Then we consider the implications of antiretroviral therapies on vitamin D metabolism. We finally evaluate the benefits of a vitamin D supplementation in HIV + patients.

[Gentetics, environment and determinants of autoimmune diseases]

We initiate this review article by a brief description of a few monogenic autoimmune diseases such as the APECED and the IPEX syndrome because they allow understand the fundamental mechanisms of self tolerance. Next we describe with more details the complex autoimmune diseases and discuss the recent data regarding the associated genetic and environmental factors and their modes of interaction. The conclusion of the article deals with the practical implications of this inherent complexity for the researcher and the clinician.

[The complex interactions between the origins of HIV and its epidemic, colonial activities in Africa and colonial medicine in Belgian Congo]

In this review article on the origin of HIV, we start from a historical fact which involved physicians from Liège working in Belgian Congo: the vaccination against polio of hundreds of thousands of Congolese between 1957 and 1960. We explain the genesis of an alternative hypothesis postulating that this campaign was at the origin of HIV pandemy. We show that the hypothesis is unfounded in view of genetic and epidemiological evidence on the one hand and after thorough examination of the activity reports of the Laboratoire Médical de Stanleyville on the other. In the second part of the article, we analyse the importance of other factors which might have contributed to the emergence of the pandemy. Some of these are clearly iatrogenic such as the prophylactic injections of pentamidine against trypanosomiasis, others are of demographic and sociological nature. All of them have a direct link with colonisation.

[Basic immunological knowledge for understanding monoclonal antibodies]

Antibodies (Ab) are molecules with dual functions: on the one hand, they bind to antigens (Ag) through their variable regions (Fab, "Fragment antigen binding"), located at one of their extremities; on the other hand, they recruit cells of the immune system, via the other extremity, the constant region or Fc region, which results in a selective destruction of cells that have the corresponding Ag. The capacity of recognition of Ag by Ab is unique. Ag generally have several different epitopes that all are binding sites for Ab. Ab may be classified according to their ability to recognize one single epitope or several epitopes. They are called monoclonal Ab (mAb) or polyclonal Ab, respectively. MAbs recognize the same epitope because they are issued from one single line of plasmocytes, originating from one single cell. It is the reason why they are so selective. MAbs exert complex, but unique mechanisms of action: they inhibit or activate signal transduction, and they specifically drive the immune system against target cells, such as tumoral cells. After their extensive use in fundamental and in applied research as wells as diagnostic tools, mAbs are now largely exploited in therapeutics.

[A fixed dose anti-HIV combination for the poor? Triomune]

Despite a relative global stabilization of its incidence, HIV infection remains a major threat for public health, principally in Africa where it concerns more than 22 million people and constitutes the first cause of death on the continent. To face the emergency of the HIV/AIDS epidemics on the African continent, the primary goal is to make available to all patients free and efficient antiretroviral medications. Such a goal cannot be dissociated from large scale prevention campaigns. In 2000, Triomune, one of the first fixed dose combinations of three antiretrovirals (stavudine, lamivudine & nevirapine) was launched by the Indian drug company Cipla, specialized in the production of low cost medications. Its convenient pill burden (one pill twice a day) and its very low cost (around 30 US $ per month) make Triomune an appealing solution for the treatment of HIV/AIDS in Africa. Unfortunately, Triomune presents several drawbacks (low genetic barrier, frequent side effects) and one of its constituents is not used in Europe anymore. Other first line treatments are urgently needed.

[Syphilis in 2008: practical aspects and controversies]

Rising incidence rate of syphilis is observed in economically advanced countries, particularly among homosexual men and subpopulation with low socioeconomic status. The various clinical presentations are divided into early and late stages, including neurosyphilis. The latter can occur during any stage of the disease, leading to the question "when to perform lumbar puncture", particularly in HIV positive patients. Penicillin continues to be the first-line therapy for all stages of syphilis. An alternative treatment should be considered as an exemption, after advice from a specialist. All patients require prolonged clinical and serological follow-up after treatment to rule out relapse or re-infection. The diagnosis of syphilis is an opportunity to search and treat other sexually transmitted diseases in patients and their sexual partner(s).

Chronic hepatitis C infection in a patient with bone marrow hypoplasia

Chronic hepatitis C virus (HCV) infection is associated with multifarious extra-hepatic manifestations; the most described and discussed being mixed cryoglobulinemia which is strongly related to B-cell lymphoproliferative disorders (LPDs). We present a case of chronic HCV infection and mixed cryoglobulinemia, with minimal liver involvement. The case is a 53-year-old patient who was diagnosed as having bone marrow hypoplasia at the age of three. She received several blood transfusions to normalize her haemoglobin. At the age of 31, she was diagnosed with rheumatoid arthritis on account of her diffuse joint pain and inflammation, elevated rheumatoid factor (RF) and Raynaud’s phenomenon. Twenty years later, monoclonal gammopathy of IgG Lambda (one year later, changed to IgM Kappa) was detected during a routine examination. A bone marrow biopsy showed hypoplasia, Kappa positive B-lymphocytes and low-grade malignant lymphoma cells. PCR of the bone marrow aspirate was not contributory. No treatment was initiated owing to her poor bone marrow function and she is under regular follow-up.

[Evaluation of thymopoiesis: clinical applications]

In the precedent article, we have described how T-cell generation in the thymus (thymopoiesis) may be currently evaluated through quantification by PCR of T-cell receptor excision circles (TREC) generated by intrathymic random recombination of the gene segments coding for variable parts of T-cell receptor for antigen (TCR). In hematology, TREC methodology helps in a better understanding of immune reconstitution after graft of hematopoietic stem cells: first there is a proliferation of mature T cells present in the graft, then a differentiation of naive T cells. In geriatrics, the homeostasis of the peripheral T-cell repertoire is maintained through proliferation of peripheral memory T cells rather than through thymic generation of naive T cells. In addition, TREC quantification constitutes a novel major tool for deciphering the tight control of thymopoiesis by the neuroendocrine system.

[Lipodystrophy syndrome in HIV infected patients]

Prolonged utilization of some antiretroviral drugs in patients infected by HIV can lead to the outbreak of a lipodystrophy syndrome. This syndrome is characterized by modification of fats corporal repartition, sometimes associated with metabolic disturbancies (dyslipemia and insulin resistance). Two antiretroviral classes are implicated in the pathophysiology of this syndrome, namely protease inhibitors (PIs) and nucleoside reverse transcriptase inhibitors (NRTIs). The PIs rather influence the differentiation of adipose tissue with its secretion. They are more often associated with visceral adiposity, insulin resistance and dyslipemia. The mitochondrial toxicity of the NRTIs is more frequently responsible for adipose tissue loss at the periphery. Other factors in relation to the patient influence the severity of this syndrome. Several therapeutic options are to be considered both when taking care of the patients suffering from this syndrome and when new patients are to be treated.

[Clinical evaluation of thymic function]

The essential role of the thymus is to install an extremely diverse repertoire of T lymphocytes that are self-tolerant and competent against non-self, as well as to generate self-antigen specific regulatory T cells (Treg) able to inactivate in periphery self-reactive T cells having escaped the thymic censorship. Although indirect, techniques of medical imaging and phenotyping of peripheral T cells may help in the investigation of thymic function. Nowadays however, thymopoiesis is better evaluated through quantification by PCR of T-cell receptor excision circles (TREC) generated by intrathymic random recombination of the gene segments coding for the variable parts of the T-cell receptor for antigen (TCR). The TREC methodology is very valuable in the circumstances not associated with intense proliferation or apoptosis of peripheral T lymphocytes.

[New treatments of infectious diseases over the last ten years]

This review focuses on new antibiotics, particularly for gram-positive infections, new antiretroviral drugs, new treatment of fungal infections and indications of miltefosine in the treatment of leishmaniasis.

[New approaches to the treatment of the HIV-infected patient]

HIV infection remains a major problem of public health in Belgium as well as globally. The number of new diagnosies of HIV infection in Belgium remains between two and three daily. Given the dramatic effect of antiretroviral therapy on the mortality due to HIV infection, the number of patients is constantly increasing. The different problems related to HIV care are also changing. Aging of the patients and chronic exposure to antiretroviral medications have induced new complications. We will present in this brief article several new experimental and clinical approaches in which our centre has participated during the last two years.

[A review about nephropathia epidemica]

We propose a review of history, aetiology, physiopathology, clinical features, treatment and prevention of nephropathia epidemica (NE) which represents the only form of Hantavirus infection in Belgium.

[Should the BCG vaccine still be recommended?]

The BCG vaccine has demonstrated its efficacy to protect young children from severe extrapulmonary forms of tuberculosis. Nevertheless, the immunity induced by the vaccine disappears in adults and cannot be boosted by readministration of BCG. Adverse effects of BCG are rare, but potentially dangerous (i.e. disseminated vaccinal infections) and they justify the fact that BCG should not be administered anymore in Western European countries where the incidence of pediatric tuberculous meningitis is very low. The vaccine is still recommanded for children living in countries with high tuberculosis prevalence and for resident children leaving Belgium for these countries.