Hepatocellular Carcinoma in Mongolia Delineates Unique Molecular Traits and a Mutational Signature Associated with Environmental Agents

PURPOSE

Mongolia has the world's highest incidence of hepatocellular carcinoma (HCC), with ∼100 cases/100,000 inhabitants, although the reasons for this have not been thoroughly delineated.

EXPERIMENTAL DESIGN

We performed a molecular characterization of Mongolian (n = 192) compared with Western (n = 187) HCCs by RNA sequencing and whole-exome sequencing to unveil distinct genomic and transcriptomic features associated with environmental factors in this population.

RESULTS

Mongolian patients were younger, with higher female prevalence, and with predominantly HBV-HDV coinfection etiology. Mongolian HCCs presented significantly higher rates of protein-coding mutations (121 vs. 70 mutations per tumor in Western), and in specific driver HCC genes (i.e., APOB and TSC2). Four mutational signatures characterized Mongolian samples, one of which was novel (SBS Mongolia) and present in 25% of Mongolian HCC cases. This signature showed a distinct substitution profile with a high proportion of T>G substitutions and was significantly associated with a signature of exposure to the environmental agent dimethyl sulfate (71%), a 2A carcinogenic associated with coal combustion. Transcriptomic-based analysis delineated three molecular clusters, two not present in Western HCC; one with a highly inflamed profile and the other significantly associated with younger female patients.

CONCLUSIONS

Mongolian HCC has unique molecular traits with a high mutational burden and a novel mutational signature associated with genotoxic environmental factors present in this country.

Viral and immune factors associated with successful treatment withdrawal in HBeAg-negative chronic hepatitis B patients

BACKGROUND & AIMS

Factors associated with a successful outcome upon nucleos(t)ide analogue (NA) treatment withdrawal in HBeAg-negative chronic hepatitis B (CHB) patients have yet to be clarified. The objective of this study was to analyse the HBV-specific T cell response, in parallel with peripheral and intrahepatic viral parameters, in patients undergoing NA discontinuation.

METHODS

Twenty-seven patients without cirrhosis with HBeAg-negative CHB with complete viral suppression (>3 years) were studied prospectively. Intrahepatic HBV-DNA (iHBV-DNA), intrahepatic HBV-RNA (iHBV-RNA), and covalently closed circular DNA (cccDNA) were quantified at baseline. Additionally, serum markers (HBV-DNA, HBsAg, HBV core-related antigen [HBcrAg] and HBV-RNA) and HBV-specific T cell responses were analysed at baseline and longitudinally throughout follow-up.

RESULTS

After a median follow-up of 34 months, 22/27 patients (82%) remained off-therapy, of whom 8 patients (30% of the total cohort) lost HBsAg. Baseline HBsAg significantly correlated with iHBV-DNA and iHBV-RNA, and these parameters were lower in patients who lost HBsAg. All patients had similar levels of detectable cccDNA regardless of their clinical outcome. Patients achieving functional cure had baseline HBsAg levels ≤1,000 IU/ml. Similarly, an increased frequency of functional HBV-specific CD8+ T cells at baseline was associated with sustained viral control off treatment. These HBV-specific T cell responses persisted, but did not increase, after treatment withdrawal. A similar, but not statistically significant trend, was observed for HBV-specific CD4+ T cell responses.

CONCLUSIONS

Decreased cccDNA transcription and low HBsAg levels are associated with HBsAg loss upon NA discontinuation in patients with HBeAg-negative CHB. The presence of functional HBV-specific T cells at baseline are associated with a successful outcome after treatment withdrawal.

LAY SUMMARY

Nucleos(t)ide analogue therapy can be discontinued in a high proportion of chronic hepatitis B patients without cirrhosis. The strength of HBV-specific immune T cell responses may contribute to successful viral control after antiviral treatment interruption. Our comprehensive study provides in-depth data on virological and immunological factors than can help guide individualised therapy in patients with chronic hepatitis B.

Chronic genotype 1 hepatitis C along with cirrhosis drives a persistent imprint in virus-specific CD8+ T cells after direct-acting antiviral therapies

Chronic hepatitis C virus (HCV) infection impairs HCV CD8⁺ T-cell responses, while it could influence immune responses towards unrelated viruses/vaccines (e.g. cytomegalovirus, CMV, and influenza, Flu). The aim of our study was to delineate whether restoration of these virus-specific CD8⁺ T cells occurs after direct-acting antiviral (DAA) therapies and particularly in patients with cirrhosis. We performed longitudinal analysis (baseline, week 4, follow-up [FU] 12 and FU48) of virus-specific CD8⁺ T cells by multicolour flow cytometry in HCV-cirrhotic patients undergoing DAA therapy (n = 26) after in vitro expansion with immunodominant HCV, CMV and Flu epitopes restricted by HLA-A*02. HCV noncirrhotic patients (n = 9) and healthy individuals (n = 10) served as controls. We found that the proliferative capacity of HCV-specific CD8⁺ T cells increased from baseline up to FU48 in a significant proportion of cirrhotic and noncirrhotic patients. Nevertheless, these cells remained poor cytokine producers in both patient groups, regardless of the down-regulation of inhibitory co-regulatory receptors in HCV-cirrhotic patients at FU48. Likewise, high expression levels of these exhaustion markers were detected in CMV-/Flu-specific CD8⁺ T cells in HCV-cirrhotic patients at all time points, albeit without affecting their proliferative capacity or cytokine production. We conclude that DAA therapies induce restoration of the proliferative capacity of HCV-specific CD8⁺ T cells. However, these cells remain phenotypically and functionally impaired. Contrarily, the 'exhausted' phenotype in CMV-/Flu-specific CD8⁺ T cells in HCV-cirrhotic patients did not associate with their functions. Larger studier with longer follow-up may elucidate whether this complex interplay influences the outcome of cirrhotic patients.

From ICD10 to ORPHAcodes: paving the way towards improved identification systems for rare diseases

Background

The International Classification of Diseases 10th revision (ICD10) and its clinical modification (ICD10CM) are commonly used for the identification of diseases occurrence worldwide. In Spain, diagnoses are coded with its Spanish version (ICD10ES) since 2016 regardless of the prevalence of diseases. Rare diseases (RDs) are scrambled among common diseases in ICD10 and its derivatives and many RDs dońt have a specific ICD10 code, delaying a proper identification. Orphanet developed a classification system specific for RDs called ORPHAcode. This study aims to characterize whether ICD10ES mapping to ORPHAcodes improves RDs identification and which kind of disorders would benefit the most.

Methods

95% of the disorder level ORPHAcodes indexed at Orphanet was mapped to codes from 20 ICD10ES chapters by comparing the descriptors associated in both classifications. ORPHAcodes were then clustered based on their assigned ICD10ES chapter and the redundancy of each individual ICD10ES code was calculated by counting the ORPHAcodes they mapped to. 3 groups were established: Group 1 (1 ORPHAcode per ICD10ES), Group 2 (between 2-49 ORPHAcodes per ICD10ES) and Group 3 (≥50 ORPHAcodes per ICD10ES).

Results

5588 ORPHAcodes were correlated to 1677 ICD10ES codes. 1051 were group 1, 3261 group 2 (615 ICD10ES) and 1276 group 3 (11 ICD10ES). Most of the Orphacodes correlated to “Q” (>40%), “G” (>14%) and “E” (>12%) chapters of ICD10ES. Regarding specificity, “G” and “Q” were also the only chapters including group 3 ORPHAcodes, while less than 10% of the ORPHAcodes linked to these chapters were in group 1.

Conclusions

New and improved ICD10ES codes are required because just 20% of all ORPHAcodes studied were into group 1. Especial care should be put on the two majoritarian chapters, “Q:Congenital Anomalies” and “G:Nervous System”, that show the lowest specificity for RDs. Complementary use of ORPHAcodes would improve the identification and registry of RDs either.

Funded: Project RD-CODE

Key messages

The lack of a specific chapter for Rare Diseases in the InternationaI Classification of Diseases hinders their identification and therefore their study. Direct mapping between ICD10 and ORPHAcodes or the use of ORPHAcodes for diagnoses codification of Rare Diseases would enable better detection and epidemiological analysis.

Cirrhosis Hampers Early and Rapid Normalization of Natural Killer Cell Phenotype and Function in Hepatitis C Patients Undergoing Interferon-Free Therapy

Background: Chronic hepatitis C virus (HCV) infection impairs natural killer (NK) cell phenotype and function. Whether restoration of NK cells occurs after successful interferon (IFN)-free therapies remains a controversial issue. Aim: To analyze how HCV-related liver cirrhosis impacts changes in NK cells prior and post-IFN-free therapies. Methods: NK cell analysis by multicolor flow cytometry was performed in HCV-infected patients with (n = 17) and without (n = 14) cirrhosis at baseline, week 4 during therapy, and weeks 12 and 48 after the end of therapy (FU12 and FU48, respectively). Non-HCV cirrhotic patients (n = 12) and healthy individuals (n = 12) served as controls. Results: At baseline, HCV cirrhotic patients presented an altered distribution of NK subsets (CD56dim and CD56bright) with higher expression of NKp46, HLA-DR, NKp30, KIR2DL2/L3, NKG2A, and CD85j receptors compared to healthy controls. All frequencies normalized by FU48, except for CD85j+ cells. Likewise, substantial alterations were detected in NK cell function assessed by (i) signal transducer and activator of transcription 1 (STAT1) and phosphorylated levels of STAT1 and STAT4, (ii) degranulation (CD107a), (iii) cytotoxicity [tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)], and (iv) cytokine production [IFN-γ and tumor necrosis factor-α (TNF-α)]. Of note, NK cell function at FU48 remained partially impaired. In contrast, non-cirrhotics showed normal baseline frequencies of HLA-DR-, NKG2A-, and CD85j-expressing NK cells. Importantly, altered baseline frequencies of NK cell subsets and NKp46+ CD56dim cells, as well as NK cell function, were rapidly and completely restored. Conclusions: NK cell phenotype alterations persist after HCV eradication in cirrhotic patients, while their function is only partially restored, compromising immune restoration and immunosurveillance.

Low seroprevalence and zero incidence rate of hepatitis E in men who have sex with men during a hepatitis A outbreak

Hepatitis E virus (HEV) and hepatitis A virus (HAV) are both secreted in feces. Despite HEV transmission in Europe is mainly zoonotic, person-to-person transmission has not been completely excluded. Men who have sex with men (MSM) constitute a high-risk group for HAV mostly due to oral sex. We investigated the potential transmission of HEV during an acute hepatitis A (AHA) outbreak mainly affecting MSM. One hundred and two patients were diagnosed with AHA. Sixty-nine (68%) self-reported to be MSM, 75% of whom had high-risk sexual behaviors and 46% had suffered previous sexually transmitted diseases. We collected serum from 85 (83%) patients during AHA. HEV-IgG seroprevalence was not different among MSM (7%) compared with non-MSM (8%) patients. Two patients had positive anti-HEV-IgM, but all samples tested negative for HEV-RNA. These results suggest that HEV does not spread by sexual contact or person-to-person in our area.

[Pathological hip fracture of pediatric age. Revision of the cystic angiomatosis of the bone]

INTRODUCTION

Bone cystic angiomatosis is a disease with only 200 cases described, based on angiomatous nonmalignant proliferation, in bone tissue and viscera. It focuses on pelvis, long bones and scapular waist. Clinical evolution ranges from self-limiting forms to massive aggressive osteolysis (Gorham-Stout).Its diagnosis is of exclusion, with nonspecific clinical, radiological (lytic images) and histopathological findings.

CLINICAL CASE

Our study is based on the clinical case of a 14-year-old man diagnosed with bone cystic angiomatosis, with disseminated bone involvement, who came to our center for pain and functional impotence in the right hip, diagnosing a pertrochanteric fracture. It was operated by open reduction and osteosynthesis with four-hole VERSA sliding plate screw. An allogeneic graft of cancellous bone was used from femoral head. The evolution was satisfactory, with ambulation at full load per month without requiring analgesic medication and control X-ray at eight months that showed signs of complete integration of the graft. The analgesic pain scale (visual analogue scale) showed a score of 2/10 per month.

DISCUSSION

There is controversy regarding the treatment of these fractures by osteosynthesis with bone graft. We are facing a case without serious clinical criteria, but with multiple foci of osteolysis. It was decided not to intervene prophylactically the contraleteral hip, since it is asymptomatic and there are different patterns of evolution described in the literature and risks in surgery.

Anti-viral therapy can be delayed or avoided in a significant proportion of HBeAg-negative Caucasian patients in the Grey Zone

BACKGROUND

Grey Zone (GZ) is an ill-defined situation including patients falling between inactive carrier (IC) state and HBeAg-negative chronic hepatitis B (HBeAg-negative CHB).

AIMS

To assess the long-term outcomes of GZ patients compared to IC in the absence of treatment.

METHODS

Retrospective analysis of 287 IC and GZ HBeAg-negative patients. Patients were classified into 4 groups at baseline: HBV-DNA <2000 IU/mL and ALT <40 U/L (IC), HBV-DNA <2000 IU/mL and ALT 40-80 U/L (GZ-1), HBV-DNA 2000-20 000 IU/mL and ALT <40 U/L (GZ-2) or ALT 40-80 U/L (GZ-3). Data were also analysed using AASLD ALT criteria.

RESULTS

After a median follow-up of 8.2 (5-19) years, HBsAg loss occurred in about 15% ICs or GZ patients. Transition into IC state occurred in 40% of GZ patients. DNA fluctuations >2000 IU/mL correlated inversely with transition into IC and HBsAg loss. HBsAg levels were significantly lower in ICs than in GZ patients (338 IU/mL [20-3269] vs 5763 IU/mL [2172-17 754]; P < 0.05). Among the latter group, there was an increasing gradient of HBsAg levels from GZ-1 to GZ-3 patients (P < 0.05). HBeAg-negative CHB occurred in only 18 (6.3%) GZ patients. No patient developed cirrhosis nor advanced fibrosis. ALT/HBV-DNA fluctuations and HBeAg-negative CHB development were more frequent in genotype B/C patients, whereas HBsAg loss occurred only in genotype A/D patients.

CONCLUSIONS

Most Caucasian GZ patients present excellent long-term outcomes in the absence of treatment, with a high rate of HBsAg loss and low rate of progression to HBeAg-negative CHB. HBV-genotyping and HBsAg levels could help to predict outcomes and better classify GZ patients.

[Postoperative pain control with intrathecal morphine in patients undergoing vertebral fusion with instrumentation]

BACKGROUND

Proper postoperative pain management in patients undergoing vertebral arthrodesis with instrumentation is essential to reduce postoperative morbidity and mortality. Intrathecal morphine may provide effective analgesia minimizing the dose required and adverse side effects. The objective of this study is to assess the efficacy of intrathecal morphine to control postoperative pain in patients undergoing vertebral arthrodesis with instrumentation.

MATERIAL AND METHODS

A prospective randomized trial was conducted; it included 46 patients who underwent vertebral fusion with instrumentation. Patients were randomly divided into two groups: one of them received a 0.003 mg/kg dose of intrathecal morphine before closing the surgical wound. The following parameters were recorded during the postoperative period: respiratory rate, PCO₂, PO₂, need for adjuvant anesthesia and subjective pain assessment with the visual analog scale (VAS), at 6, 24 and 48 hours after the surgery. The results were analyzed with non-parametric tests.

RESULTS

Patients who received intrathecal morphine had a statistically significant decrease in postoperative pain within 48 hours after the surgery, with a mean VAS score close to 3. In 24.1 percent of patients had complications associated with the use of morphine chloride, such as nausea and vomiting, without any statistically significant differences compared with the control group.

CONCLUSIONS

Intrathecal morphine is a safe and effective treatment option to control early postoperative pain in patients undergoing vertebral fusion with instrumentation. This leads to a more convenient and quick recovery.

[Radiologic study on postnatal ossification of the first metatarsal bone]

BACKGROUND

Classical descriptions of the ossification of the first metatarsal bone show the existence of a single proximal secondary ossification nucleus, mimicking the typical ossification of a phalanx. However, there are studies that show the presence of a second distal ossification nucleus and discuss its nature: epiphysis or pseudoepiphysis. The objective of the study is to establish the prevalence of such distal nucleus, determine its role in the growth of the radius and its relation with different qualitative variables.

MATERIAL AND METHODS

We conducted a retrospective study that included 971 dorsoplantar images from 225 patients. We analyzed the presence of such nucleus, the age of appearance and closure, the relation with different qualitative variables and their contribution to the longitudinal growth of the first metatarsal bone.

RESULTS

The distal ossification nucleus appears in 40% of all images and in 81.1% of cases ages 4-7 years. Mean age of appearance is 3.07 years, while physeal closure occurs at a mean of 7.67 years. We found a significantly higher frequency of physeal closure in children, patients with Egyptian type foot, flat foot, and index-plus and Egyptian type foot combinations. The definitive length of the first metatarsal bone is greater in patients with a distal ossification nucleus.

CONCLUSIONS

We may state the presence of the distal ossification nucleus of the first metatarsal bone that behaves as a fertile growth cartilage.

Adherence to the Mediterranean dietary pattern and heart rate in the SUN project

BACKGROUND

A higher heart rate has been related to an increase of total and cardiovascular mortality. The aim of this study was to assess the relation between adherence to the Mediterranean diet and heart rate.

DESIGN

The SUN project is an ongoing multipurpose cohort study based on university graduates from Spain.

METHODS

This cross-sectional study included 15,863 participants of the SUN project. Adherence to the Mediterranean dietary pattern was assessed through a validated 136-item food frequency questionnaire and calculated according to the 9-point score proposed by Trichopoulou. Multiple linear regression models were fitted to assess the relationship between adherence to the Mediterranean dietary pattern and heart rate and 95% confidence intervals were calculated.

RESULTS

The multivariable-adjusted models revealed that participants with a high adherence (7--9 points) to the Mediterranean dietary pattern had a heart rate 2.2 bpm (95% CI 1.4-3.1) lower than participants with a low adherence (0--2 points).

CONCLUSIONS

Adherence to the Mediterranean dietary pattern seems to be related to a lower heart rate.

[Compliance with current dietary recommendations and geographical variability of diet in women participating in 7 screening programs for breast cancer in Spain]

INTRODUCTION

A healthy diet is especially important during menopause, a period which increases the risk of various health problems. We analyzed the diet of periand postmenopausal Spanish women and the degree of compliance with current recommendations.

MATERIAL AND METHODS

We studied 3574 women 45-68 years old who attended breast cancer screening programmes in 7 centres (A Coruña, Barcelona, Burgos, Palma de Mallorca, Pamplona, Valencia and Zaragoza). Diet information was collected using a food frequency questionnaire validated for the Spanish population. For the assessment of compliance with current guidelines we used the recommendations by the Spanish Society of Community Nutrition for food groups intake and by the Spanish Federation of Nutrition, Food and Dietetics for energy, vitamins and minerals intake.

RESULTS

The 29% of women were obese and 42% overweight. The average caloric intake was 2.053 kcal (SD 480). The general energy profile was: 43% of the energy from the carbohydrates, 36% from fats, and 20% from proteins. There was a low vitamin D intake in all centres of the study, with an overall mean intake of 2.14 mg/day. A deficit of vitamin E intake in A Coruña and Burgos was also detected. Intake of dairy products and vegetables was high in all the study centers. The consumption of fruits and vegetables was very heterogeneous, with high intakes observed in Mallorca and Valencia and low for both food groups in A Coruña. The olive oil intake was high in all centers except Burgos with 74.3% of the women studied below the recommended 3 servings per day.

CONCLUSIONS

A diet with less fat and protein and a higher consumption of vegetables, nuts and foods rich in carbohydrate might balance the energy intake and improve the quality of the diet correcting the low intakes of vitamins D and E. These recommendations are especially important in cities far from the Mediterranean coast where more breaches have been detected over the current recommendations with a lower adherence to the Mediterranean diet.

Mediterranean diet and the incidence of cardiovascular disease: a Spanish cohort

BACKGROUND AND AIM

The Mediterranean diet is considered a model for healthy eating. However, prospective evidence in Mediterranean countries evaluating the relationship between this dietary pattern and non-fatal cardiovascular events is scarce. The aim of the present study was to evaluate the association between the adherence to the Mediterranean diet and the incidence of fatal and non-fatal cardiovascular events among initially healthy middle-aged adults from the Mediterranean area.

METHODS AND RESULTS

We followed-up 13,609 participants (60 percent women, mean age: 38 years) initially free of cardiovascular disease (CVD) during 4.9 years. Participants were part of a prospective cohort study of university graduates from all regions of Spain. Baseline diet was assessed using a validated 136-item food-frequency questionnaire. A 9-point score was used to appraise adherence to the Mediterranean diet. Incident clinical events were confirmed by a review of medical records. We observed 100 incident cases of CVD. In multivariate analyses, participants with the highest adherence to the Mediterranean diet (score>6) exhibited a lower cardiovascular risk (hazard ratio=0.41, 95% confidence interval [CI]: 0.18-0.95) compared to those with the lowest score (<3). For each 2-point increment in the score, the adjusted hazard ratios were 0.80 (95% CI: 0.62-1.02) for total CVD and 0.74 (0.55-0.99) for coronary heart disease.

CONCLUSIONS

There is an inverse association between adherence to the Mediterranean diet and the incidence of fatal and non-fatal CVD in initially healthy middle-aged adults.

Development of a dispersive liquid–liquid microextraction method for organophosphorus flame retardants and plasticizers determination in water samples

A fast, inexpensive and efficient sample preparation method for the determination of 10 organophosphorus compounds in water samples is presented. Analytes were extracted using the dispersive liquid-liquid microextraction (DLLME) technique and determined by gas chromatography with nitrogen-phosphorus detection (GC-NPD). The influence of several variables (e.g. type and volume of dispersant and extraction solvents, ionic strength, shaking time and mode, etc.) on the performance of the sample preparation step was carefully evaluated. Under final working conditions, 1 mL of acetone containing a 2% of 1,1,1-trichloroethane (20 microL) was added to 10 mL of water with 20% of sodium chloride. The ternary mixture was centrifuged at 3500 rpm to allow phase separation. After removing the aqueous supernatant, an aliquot of the settled extract was injected in the GC-NPD system. Under the above conditions, the method provided enrichment factors between 190 and 830 times (depending on the considered compound), relative standard deviations below 10%, except for tris(2-ethylhexyl) phosphate (TEHP), and quantification limits between 0.01 and 0.08 ng/mL. Matrix effects were assessed using different water samples, and accuracy was evaluated by comparison with solid-phase microextraction.

[Axolemmal transporters for neurotransmitter uptake]

INTRODUCTION AND OBJECTIVE

Neurotransmission is a fundamental process in interneuronal communication. It starts with the release of the neurotransmitter following a nerve impulse and ends either by uptake by specific specific transporters or by metabolization to an inactive compound. In this review we will consider the molecular, ion dependence and electrogenic properties of the axolemal transporters for neurotransmitters and also the pathological consequences of their impairment as well as the drugs that can interact with them.

DEVELOPMENT

Most axolemmal transporters have been cloned and grouped into two large families according to their molecular characteristics and electrogenic properties: 1. Those dependent on Na+/Cl- include transporters of GABA, noradrenaline, dopamine, serotonin, choline, proline, betaine, glycine and taurine, and 2. Those dependent on Na+/K+, which include the transporters of glutamate, alanine, serine and cysteine.

CONCLUSIONS

The clonation of transporters has permitted (and will continue to permit) the correlation of molecular alterations of transporters with different neuro-degenerative disorders (e.g. multiple sclerosis, Parkinson's disease, Alzheimer's disease), with brain lesions (e.g. cerebral ischemia, status epilepticus) and with psychiatric alterations (e.g. schizophrenia, depression). In this respect, chemical synthesis of new selective drugs which interact with the different systems for uptake of neurotransmitters will offer new approaches to the treatment of many disorders of the central nervous system which still have no satisfactory drug treatment.

A prospective study of adverse drug reactions in hospitalized children

AIMS

There are few publications of adverse drug reactions (ADRs) among paediatric patients, though ADR incidence is usually stated to be higher during the first year of life and in male patients. We have carried out a prospective study to assess the extent, pattern and profile risk for ADRs in hospitalized patients between 1 and 24 months of age.

METHODS

An intensive events monitoring scheme was used. A total of 512 successive admissions to two medical paediatric wards (47 beds) were analysed. The hospital records were screened daily during two periods (summer, 105 days and winter, 99 days), and adverse clinical events observed were recorded.

RESULTS

A total of 282 events were detected; of these, 112 were considered to be manifestations of ADRs. The cumulative incidence was 16.6%, no differences being observed between periods. Although there were no differences between patients under and over 12 months of age, risk was found to be significantly higher among girls compared with boys (RR=1.66, 95% CI 1.03-2.52). The gastro-intestinal system was most frequently affected. The therapeutic group most commonly implicated was anti-infective drugs and vaccines (41.5%). The ADRs were mild or moderate in over 90% of cases. A consistent relationship was noted between the number of drugs administered and the incidence of ADRs.

CONCLUSIONS

Hospitalized patients exhibited an ADR risk profile that included female sex and the number of drugs administered. No particular age predisposition was observed. The most commonly prescribed drugs are those most often implicated in ADRs in paediatric patients.

A prospective study of adverse drug reactions as a cause of admission to a paediatric hospital

1. A total of 512 consecutive paediatric hospital admissions of children 2 years old or less were evaluated to assess the extent and pattern of admission caused by suspected adverse drug reactions (ADRs). the proportion of suspected ADRs related to hospital admissions was 4.3%. 2. The organ-systems most commonly implicated were the central nervous system (40.5%), digestive system (16.7%), and skin and appendages (14.3%). Together, they accounted for 71.5% of admissions attributed to ADRs. The most common clinical manifestations inducing admission were convulsions (4 cases), dizziness (4), vomiting (3), and tremor, fever, itching and apnoea (2 cases each). 3. The four classes of drugs most frequently suspected in admissions due to ADRs were respiratory drugs (35%), anti-infective agents (25%), drugs active on the central nervous system (15%) and drugs used in dermatology (10%). The most common drugs related to ADRs were a combination of chlorpheniramine, diphenhydramine, phenylephrine, guaiphenesin and salicylic acid (4 cases), followed by fenoterol, adrenaline, paracetamol, DTP vaccine and antipolio vaccine (2 cases each). 4. There were no significant differences between children older and younger than 1 year (odds ratio 0.89; 95% CI 0.37-2.17) or between the sexes as regards hospital admittance due to suspected ADRs (odds ratio 1.94; 95% CI 0.72-5.42). 5. The results of this kind of study may be influenced by patterns of drug utilization. Nevertheless, the lack of specific studies of drug effects in young children makes it desirable to carry out pharmacoepidemiological studies in this age group.