IGF1 and PPARG polymorphisms are associated with reduced estimated glomerular filtration rate in a cohort of children and adolescents with type 1 diabetes

INTRODUCTION

Several genetic loci have been associated with diabetic nephropathy; however, the underlying genetic mechanisms are still poorly understood, with no robust candidate genes identified yet.

AIM

We aimed to determine whether two polymorphisms, previously associated with renal decline, influence kidney impairment evaluating their association with markers of renal function in a pediatric population with type 1 diabetes (T1D).

MATERIAL AND METHODS

Renal function was evaluated by glomerular filtration rate (eGFR) and albumin-to-creatinine ratio (ACR) in a cohort of pediatric subjects with T1D (n = 278). Risk factors for diabetes complications (diabetes duration, blood pressure, HbA1c) were assessed. The IGF1 rs35767 and PPARG rs1801282 SNPs were genotyped by TaqMan RT-PCR system. An additive genetic interaction was calculated. Association analysis between markers of renal function and both SNPs or their additive interaction were performed.

RESULTS

Both SNPs showed a significant association with eGFR: the A allele of rs35767 or the C allele of rs1801282 were associated to reduced eGFR compared to G alleles. Multivariate regression analysis adjusted for age, sex, z-BMI, T1D duration, blood pressure and Hba1c values showed that the additive genetic interaction was independently associated with lower eGFR (β = -3.59 [-6.52 to -0.66], p = 0.017). No associations were detected between SNPs, their additive interaction and ACR.

CONCLUSIONS

These results provide new insight into the genetic predisposition to renal dysfunction, showing that two polymorphisms in IGF1 and PPARG genes can lead to a reduction in renal filtration rate leading these patients to be exposed to a higher risk of early renal complications.

Risk factors for pre-clinical atherosclerosis in adolescents with type 1 diabetes

AIMS

To assess whether, besides "traditional" risk factors, overall oxidative stress, oxidized lipoproteins, and glycemic variability are associated with early macro-vascular damage in type 1 diabetes (T1D).

METHODS

In 267 children/adolescents with T1D (130 girls, age 9.1-23.0 years) we evaluated: derivatives of reactive oxygen metabolites [d-ROMs], serum total antioxidant capacity [TAC] and oxidized LDL-cholesterol [oxLDL]; markers of early vascular damage (Lipoprotein-associated phospholipase A2 [Lp-PLA2], z-score of carotid intima-media thickness [z-cIMT] and carotid-femoral pulse wave velocity [z-PWV]); CGM metrics of four weeks preceding the visit, central systolic/diastolic blood pressures (cSBP/cDBP), and HbA1c, z-score of BP (z-SBP/z-DBP) and circulating lipids longitudinally collected since T1D onset.. Three general linear models were built with z-cIMT, z-PWV adjusted for current cDBP, and Lp-PLA2 as independent variables.

RESULTS

The z-cIMT was associated with male gender (B = 0.491, η² = 0.029, p = 0.005), cSBP (B = 0.023, η² = 0.026, p = 0.008) and oxLDL (B = 0.022, η² = 0.022, p = 0.014). The z-PWV was associated with diabetes duration (B = 0.054, η² = 0.024, p = 0.016), daily insulin dose (B = 0.52, η² = 0.018, p = 0.045), longitudinal z-SBP (B = 0.18, η² = 0.018, p = 0.045) and dROMs (B = 0.003, η² = 0.037, p = 0.004). Lp-PLA2 was associated with age (B = 0.221, η² = 0.079, p = 3*10^-6), oxLDL (B = 0.081, η² = 0.050, p = 2*10^-4), longitudinal LDL-cholesterol (B = 0.031, η² = 0.043, p = 0.001) and male gender (B = -1.62, η² = 0.10, p = 1.3*10⁷).

CONCLUSIONS

Oxidative stress, male gender, insulin dose, diabetes duration and longitudinal lipids and blood pressure, contributed to the variance of early vascular damage in young patients with T1D.

Oral Microbiota in Children and Adolescents with Type 1 Diabetes Mellitus: Novel Insights into the Pathogenesis of Dental and Periodontal Disease

The oral microbiota can be influenced by multiple factors, but only a few studies have focused on the role of glycemic control in determining early alterations of oral microbiota and their association with pathogenesis of both periodontitis and caries. The aim of this study is to evaluate the interplay between bacteria composition, oral hygiene, and glycemic control in a cohort of children with T1D. A total of 89 T1D children were enrolled (62% males, mean age: 12.6 ± 2.2 years). Physical and clinical characteristics, glucometabolic parameters, insulin treatment, and oral hygiene habits data were collected. Microbiological analysis was performed from saliva samples. A high prevalence of cariogenic and periodontopathogens bacteria in our cohort was detected. In particular, in all subjects Actinomyces spp., Aggregatibacter actinomycetemcomitans, Prevotella intermedia, and Lactobacillus spp. were isolated. S. mutans was found in about half of the analyzed sample (49.4%), in particular in patients with imbalance values of glycemic control. Moreover, a higher presence of both S. mutans and Veillonella spp. was detected in subjects with poorer glycemic control, in terms of HbA1c, %TIR and %TAR, even adjusting for age, sex, and hygiene habits as covariates. Virtuous oral hygiene habits, such as frequency of toothbrush changes and professional oral hygiene, negatively correlated with the simultaneous presence of Tannerella forsythia, Treponema denticola, and Porphyromonas gingivalis, red complex bacteria. Our study shows it is crucial to pay attention to glycemic control and regular oral hygiene to prevent the establishment of an oral microbiota predisposing to dental and periodontal pathology in subjects with T1D since childhood.

FADS cluster variants are associated with insulin sensitivity in children and adolescents with overweight and obesity

Changes in the desaturation activity of LC-PUFAs may influence insulin sensitivity by modulating the relative abundance of omega-3. The aim of this cross-sectional study was to assess the association between genetic variants of fatty acid desaturase cluster genes (FADS1, FADS2, FADS3) and insulin sensitivity in a cohort of children and adolescents with obesity. Anthropometric evaluation, lipid profile, glucose metabolism parameters and the genotype of rs1535 on FADS2 gene were assessed. In 162 obese children and adolescents (12.6 ± 2.3 years; BMI 30.9 ± 7.3), we found a significant association between an index of insulin sensitivity, i.e., Matsuda index, and rs1535 (B = -0,192; p = 0.008), BMI (B = -0,003; p < 0.001), and triglycerides (B = -0,034; p < 0.001), independent of age and sex [R² = 0.35; p = <0.001]. In conclusion, FADS cluster variants were associated with insulin sensitivity in a population of children and adolescents with obesity, contributing to identify individuals who may benefit from personalised prevention and treatment nutritional strategies since childhood.

Cardiovascular risk factors in children and adolescents with type 1 diabetes mellitus: the role of insulin resistance and associated genetic variants

INTRODUCTION

Type 1 diabetes (T1D) is associated with increased risk of cardiovascular disease. Insulin resistance is an important cardiovascular risk factor (CVRF), also in subjects with T1D, but the influence of the genetic predisposition of insulin resistance on cardiovascular risk is still unknown in T1D. We aimed to determine whether a genetic score composed of six variants, previously associated to insulin resistance and type 2 diabetes (T2D) risk, associates with insulin sensitivity and known CVRFs in children and adolescents with T1D.

MATERIALS AND METHODS

330 children and adolescents (174 males; mean age 15.7±3.5 years) with T1D were genotyped for the following genetic variants: rs1801278 (IRS1), rs1044498 (ENPP1), rs2295490 (TRIB3), rs1801282 (PPARG), rs780094 (GCKR), and rs35767 (IGF1). An additive genetic risk score (GRS) and cardiovascular risk score (CVRS) were calculated. Anthropometric, glycemic control, insulin sensitivity, blood pressure, and biochemical parameters were assessed. Multivariate regression between evaluated phenotypes and GRS were performed.

RESULTS

We found a significant association between the GRS and estimated insulin sensitivity [β=-0.027 (-0.040 to -0.013), R2=0.86, p=<0.001], diastolic blood pressure [β=0.68 (0.08-1.27), R2=0.20, p=0.026], triglycerides [β=4.26 (1.74-6.77), R2=0.13, p=0.001], waist to height ratio [β=0.003 (0.001-0.006), R2=0.75, p=0.010], non-HDL-cholesterol [β=3.63 (1.39-5.87), R2=0.12, p=0.002], and CVRS [β=0.063 (0.008-0.118), R2=0.19, p=0.025], independent of age, sex, BMI, pubertal stage, diabetes duration, HbA1c, type of treatment and total insulin requirement. The addition of the GRS to established clinical risk factors significantly improved the discriminatory capability of the regression model for predicting subjects with more CVRFs (C-statistic 0.89 [95%CI 0.84-0.95] vs. 0.83 [0.73-0.93]; p = 0.037).

CONCLUSIONS

Insulin resistance and T2D risk-associated genetic variants influence insulin sensitivity and known cardiovascular risk factors in children and adolescents with T1D.

The importance of educating subjects entitled to use an adrenaline auto-injector for self-administration

An educational program, consisting in a clear explanation of the technical aspects and use of the adrenaline auto-injection devices (AAD) and in a practical test utilizing a demonstration kit was given to 350 patients from our outpatient clinic. AAD was also distributed to 50 patients formerly followed by another allergy clinic without training. At practical control test, only 10% of the untrained patients where able to correctly use the AAD versus 80% of trained subjects. Since AAD is a life-saving procedure in severe anaphylactic episodes, this attempt to improve the ability of the patient to comply with the procedure can improve the efficacy of the treatment and eventually the patient's health.

Prevalence and incidence of reactions to insect stings in children: a reappraisal

AIM

The prevalence of systemic reactions (SR) to Hymenoptera stings in children was estimated in values lower than 1% in early studies but much higher in recent surveys. We evaluated the current prevalence and the incidence of SR and large local reactions (LLR) to Hymenoptera stings in children in Italy.

METHODS

The data on children were collected from the database of the population study on the city of Cotignola, analyzing the answers to the part of the questionnaire about Hymenoptera stings, that concerned if the subject was ever stung by apids or vespids, if there has been a SR or a LLR, and if subjects with reactions received a diagnostic evaluation and a medical treatment.

RESULTS

Of the population of 1035 children, 173 (16.7%) were stung at least one time by Hymenoptera. Of them, 5 had had a SR and 9 had had a LLR. This defines a prevalence of SR of 0.5% and of LLR of 0.9%. Only one reaction was severe. Of the 14 subjects with SR or LLR, 5 (35.7%) underwent a diagnostic evaluation and one (7.1%) was treated with venom immunotherapy. The incidence of SR in the subsequent 2 years was 0.09% in the first year and 0.08% in the second year.

CONCLUSIONS

These findings do not confirm the recent reports of an increased prevalence of Hymenoptera venom allergy in children. The incidence of SR to stings, thus far unreported for children, was very low both in the first and in the second year.

Allergy to beer in LTP-sensitized patients: beers are not all the same

BACKGROUND

Most cases of beer allergy reported so far have been associated with hypersensitivity to the non-specific lipid transfer protein (LTP). In view of the marked differences in brewing processes we assessed IgE reactivity as well as tolerance to many different beers in an allergic patient.

METHODS

A 45 year-old man hypersensitive to grass pollen, cat dander and Alternaria tenuis with a history of urticaria and dyspnoea after drinking beer and a weak skin reactivity to commercial corn extract was studied. The patient underwent SPT with 36 different brands of beer and an open challenge with those scoring negative was performed. An immunoblot analysis was carried out using 2 SPT-positive beers, 2 SPT-negative beers, and barley, wheat, and maize extracts using both patient's serum and a maize LTP-specific in-house developed polyclonal antibody from rabbit. Further, the immune reactive LTP of one beer was separated by HPLC and the chromatogram was compared to that of purified maize LTP.

RESULTS

Beer SPT scored positive in 30/36 cases. The immunoblot analysis showed IgE reactivity at about 10 kDa against the two SPT-positive beers and against maize with both patient's serum and the polyclonal anti-LTP rabbit serum, whereas the two SPT-negative beers, and barley extract scored negative. The immunodetected protein co-migrated with maize LTP.

CONCLUSION

In beer-allergic patients the diagnostic workup may point to the detection of some tolerated products that can be consumed risk-free.

Fever of unknown origin as unique symptom of an indolent mastocytosis

A 39-years-old man afferred to our hospital for a fever lasting for more than 6 months, without abnormalities at physical examination (in particular no skin alterations); a recent laboratory and instrumental investigation was ineffective and so a fever of unknown origin (FUO) was diagnosed Since he reported an history of infantile mastocytosis (usually auto-resolving) we evaluated his serum-tryptase levels that resulted of 49 ug/L (normal value 20 ug/L), raising the doubt of the presence of an active mastocytosis. The following bone marrow evaluation showed aggregates of CD117 positive cells and a c-Kit point mutation at codon D 816V confirming the diagnosis of indolent mastocytosis.The present case confirm that FUO can be caused by an otherwise asymptomatic indolent mastocytosis, thus suggesting to include the serum-tryptase level measurement in the diagnostic approach to this pathological condition, at least in selected cases.

Prevalence of allergic disorders in Italy: the Cotignola population study

BACKGROUND

The worldwide prevalence of allergic diseases such as rhinitis, asthma, and atopic dermatitis is continuously increasing, while other allergic disorders such as urticaria and angioedema are less investigated. We performed a population study evaluating the prevalence of any kind of allergic disorders.

METHODS

The entire population of 7,201 inhabitants of Cotignola (Ravenna, Italy) was surveyed by a questionnaire assessing symptoms related to rhinitis, asthma, anaphylaxis, skin symptoms and insect sting allergy as well as the features of clinical presentations, diagnosis, and treatment received.

RESULTS

Valid questionnaires were obtained by 6,676 inhabitants (92.7%). The sample was formed by 3,266 males and 3,495 females, the mean age was 45.6 years; 1,035 subjects (15.5%) were aged less than 18 years; 404 subjects (6%) had at least one episode of wheezing/breathlessness in their lifetime, and 243 of them (60.1%) had a diagnosis of asthma; 1,002 subjects (14.8%) had nose symptoms in their lifetime, and 375 of them (37.4%) had a diagnosis of allergic rhinitis or rhinoconjunctivitis. For other allergic manifestations, data were obtained from 5,730 subjects; of them, 178 (3.1%) had skin symptoms, 59 (1.1%) had oral symptoms, and 37 (0.6%) had anaphylaxis; 207 (3.6%) had reactions to insect stings. There were no significant differences in prevalence between Italians and immigrants. Only 51.7% of subjects with asthma, 46.5% of those with rhinitis, 22.7% of those with other allergies, but 97.1% of those with insect allergy, received treatment.

CONCLUSIONS

These findings confirm recent data on epidemiology of allergic diseases in Europe, particularly in Italy, and add some details on how such diseases are managed.

Shrimp allergy in Italian adults: a multicenter study showing a high prevalence of sensitivity to novel high molecular weight allergens

BACKGROUND

Shrimp is a frequent cause of food allergy worldwide. Besides tropomyosin, several allergens have been described recently.

OBJECTIVE

We investigated which allergens are involved in Italian shrimp-allergic adults.

METHODS

Sera from 116 shrimp-allergic patients selected in 14 Italian allergy centers were studied. Skin prick tests with house dust mite (HDM) as well as measurements of IgE to Pen a 1 (shrimp tropomyosin) and whole shrimp extract were performed. All sera underwent shrimp immunoblot analysis, and inhibition experiments using HDM extract as inhibitor were carried out on some Pen a 1-negative sera.

RESULTS

Immunoblots showed much variability. IgE reactivity at about 30 kDa (tropomyosin) was found in <50% of cases, and reactivity at about 67 kDa and >90 kDa was frequent. Further reactivities at 14-18, 25, 43-50, about 60 and about 80 kDa were detected. Most subjects had a history of shrimp-induced systemic symptoms irrespective of the relevant allergen protein. IgE to Pen a 1 were detected in sera from 46 (41%) patients. Skin reactivity to HDM was found in 43/61 (70%) Pen 1-negative subjects and inhibition studies showed that pre-adsorption of sera with HDM extract induced a marked weakening of the signal at >67 kDa.

CONCLUSIONS

Several allergens other than tropomyosin are involved in shrimp allergy in adult Italian patients. Some hitherto not described high molecular weight allergens seem particularly relevant in this population and their cross-reactivity with HDM allergens makes them novel potential panallergens of invertebrates.

A case of anaphylaxis: horse-fly or hymenoptera sting?

In literature it has been described a high risk of systemic reaction after blood-sucking Dyptera bites, like mosquitoes and horsefly, in people sensitive to hymenoptera. A 51 year old man, allergic to hymenoptera venom and with a history of i.v. reaction after Mueller, who has been treated with Vespula sp. ITS for the last 3 years, was stung by a yellow, black and green insect on the neck. Five minutes after the bite, he suffered generalized hitching and urticaria, oral cavity and lower limbs paresthesia, followed by lost of consciousness. At the Emergency Room he was successfully treated with adrenaline, intravenous antihistamines and corticosteroid. The description of the insect as well as the lack of the sting on the site suggested a wasp as the culprit. By studying one of these insect that has been captured by the patient, it turned out it wasn't a Vespula, but a horsefly, the Tabanus bovinus, which resembles Hymenoptera. Skin prick test and RAST for Tabanus confirmed the allergology diagnosis. In conclusion, also Tabanus bovines can cause systemic reaction up to anaphylactic shock.

The wasp-horsefly syndrome

Here are two cases of two male patients of 57 and 62 years of age, already known as allergic to stinging hymenoptera venom, who after a horsefly bite have presented a serious 3-4 degree-type Mueller classification systemic reaction. The diagnosis has been carried out clinically and after an accurate environmental anamnesis and along with prick tests and RAST, further specific entomological confirm. In literature the so called wasp-mosquito-syndrome has been indicated where hyaluronidase has been referred to as the cross allergen, between the hymenoptera venom and the mosquito saliva, which likely triggers the reaction. We believe that it is also possible to take into consideration a wasp-horsefly-syndrome as well, supposing the increased risk of anaphylactic reactions to Tabanidae bites, relatively frequent in areas with animals and streams, in subjects sensitized to stinging hymenoptera. We also suggest the possibility that in these subjects some systemic reactions are due in fact to Tabanidae bites and not so much for the failure of a possible active ITS of stinging hymenoptera.

Ventricular fibrillation after a hymenoptera sting

A 54-year-old male, who had presented 2 ventricular fibrillation (VF) episodes with post-anoxic coma and later a return to consciousness and to a sinusal rhythm after defibrillation, have been placed a ventricular intracavitary stimulator (AICD). Since all the tests including the coronarygraphy have been found normal, we have paid attention to the anamnesis revealing an Apis mellifera sting before both VF episodes, previously considered irrelevant for the absence of relevant local symptoms. Intracutaneous tests were negative to Vespula sp. and positive to A. mellifera extract at a concentration of 0.01 mug/ml. Specific IgE for A. mellifera venom presented values of 2,36 U/ml for A. mellifera and <0.35 U/ml per Vespula sp. and Polistes dominulus. The patient was then submitted to ITS with A. mellifera aqueous extract. During the RASH treatment no adverse reactions have been observed, whereas we witnessed a major adverse reaction, 3 min after the first 100 mcg maintenance dose, controlled with anti-H1 and cortisone reaction, nevertheless no reactions were observed during the 3 years the same dosage has been repeated monthly. Our case supports the hypothesis of an anaphylactic reaction as trigger of vasoconstriction in individuals affected by ventricular arrhythmia not explained with other causes such as a coronary disease, a myocardiopathy or a pharmacological toxicity. Arrhythmia can be a serious outbreak of a mediated IgE allergic reaction even without any relevant local symptoms. The diagnostics with lyophilized A. mellifera venom has been proven safe in a patient who suffered a cardiac anaphylaxis.

Safety of etoricoxib in patients with reactions to NSAIDs

BACKGROUND

Adverse reactions to nonsteroidal anti-inflammatory drugs (NSAIDs) are a frequently reported problem due to the fact that these molecules are often used for control of pain and inflammation. Although the use of selective inhibitors of cyclooxygenase (COX) 2 helps to prevent some of these adverse reactions, they can have cardiac side effects when taken for prolonged periods. Here we report the safety and tolerability of etoricoxib, a selective COX-2 inhibitor with fewer cardiovascular effects, in patients with adverse reactions to NSAIDs.

PATIENTS AND METHODS

We performed placebo-controlled oral challenge with etoricoxib in 65 patients with previous adverse reactions to NSAIDs: 13 to salicylates, 18 to arylpropionic acids, 10 to arylacetic acid, 12 to oxicam and derivates, 8 to pyrazolones, and 4 to acetaminophen (paracetamol). The reported symptoms were urticaria or angioedema in 69%, rhinitis in 3%, and 1 case of anaphylactic shock (1.5%). The challenge was done using the placebo on the first day, half dosage of etoricoxib (45 mg) on the second day, and the therapeutic dose of 90 mg on the third day. The challenge was done in the outpatient department of the hospital and the subjects were monitored for a further 4 to 6 hours after challenge.

RESULTS

Oral challenge with etoricoxib was well tolerated in 97% of the patients. Only 2 systemic reactions were reported during the challenge test.

CONCLUSION

Etoricoxib can be considered a safe molecule for those patients with previous adverse reactions to NSAIDs.

CD30 serum levels and response to hymenoptera venom immunotherapy

BACKGROUND

The glycoprotein CD30 is expressed and released by T lymphocytes that secrete type 2 helper cytokines of (T(H)2). These molecules play a role in the pathogenesis of allergic diseases. Venom immunotherapy has proven to be very effective in hymenoptera venom allergy through a shift in cytokine production from T(H)2-type cytokines to T(H)1-type cytokines.

OBJECTIVE

To evaluate the relationship between the soluble form of CD30 (sCD30) and venom immunotherapy in patients with hymenoptera venom allergy.

MATERIALS AND METHODS

sCD30 levels were assayed by enzyme-linked immunosorbent assay in the sera of 61 healthy controls and 14 patients with hymenoptera venom allergy who had undergone immunotherapy before treatment and 1,3, and 12 months after treatment started. Nine patients were allergic to Apis venom, 4 to Vespula venom, and 1 to Polistes venom.

RESULTS

CD30 serum levels (median, interquartile range) were significantly higher in venom-allergic patients before treatment (33.6 U/mL; 14.8-61.6) than in controls (9.7 U/mL, 1.9-21.3) (P < .000). These levels decreased progressively during treatment in all patients except 2 (P < .000). At the third month of therapy, the levels reached statistical significance in comparison with baseline.

CONCLUSIONS

This study shows that sCD30 levels are significantly higher in patients with hymenoptera venom allergy and indirectly confirms a preferential T(H)2-type cytokine production in these patients. sCD30 expression decreases during immunotherapy, thus confirming the immunomodulatory role of this treatment in promoting a shift to T(H)1-type cytokines.

Focal nodular hyperplasia after busulfan treatment

The case of a 48-year-old woman in whom focal nodular hyperplasia of the liver developed after busulfan therapy was administered for essential thrombocytosis is described. Focal nodular hyperplasia is a reactive disorder related to a circulation disorder. The close temporal relation between the haematological disease, busulfan treatment and the appearance of hyperplastic diseases of the liver in our patient supports the possibility that the association of the events might not be casual.

Anaphylactic shock to Argas reflexus bite

Anaphylaxis is a severe, life-threatening allergic reaction, affecting both children and adults. The occurrence of anaphylaxis is not as rare as generally believed (1.21% to 15.04% of the US population). Often the cause of this reaction remain unknown, mainly due to the difficulty in defining the outbreaking causes. Herein, we describe an interesting case of a patient, who developed an anaphylactic reaction after the bite of a pigeon tick. During the last 2 years, in wintertime, the patient often came to the emergency room for general rash and swelling, hypotension and tachycardia preceded by itching and general distress. Notably, the symptoms manifested themselves as night fell. In two particular occasions the patient reached the hospital in a state of shock. After another episode of general swelling, the patient was invited to examine her domestic environment. She brought us some parasites, collected at home, particularly on the bed. A morphological examination by entomologists proved these parasites to belong to Argas reflexus (Arg.r.), one of the 31 species of soft ticks. The presence of specific IgE to a protein secreted by the Arg.r. salivary glands was in favour of immediate-type systemic reaction, as supposed by the clinical history.

Effects of hydroclimatic anomalies on bacteriological quality of the Middle Paraná River (Santa Fe, Argentina)

Lenitic and lotic aquatic environments were studied in the Middle Paraná River basin, one of the largest rivers of the world (basin: 1,510,000 km2, length: 2,570 km). The Paraná River (S 31 degrees 42' 04"; W 60 degrees 29' 39"), during El Niño-Southern Oscillation (ENSO) (1997-1998), registered maximum flows of 29,962 m3 s(-1) (more than twice the mean flow) and also positive pluvial anomalies (A) (from +120 mm to +161 mm). However, concentrations of Escherichia coli remained low, with values similar to the mean (p > 0.05) (1.3802 log10cfu/100 ml). Only a maximum peak (1.903 log10cfu/100 ml), significantly higher than the mean (p < 0.0001), was detected during the ascending phase of the flood pulse. During La Niña (September 1999-March 2000; Q = 11,255 m3 s(-1); A = -78 mm to -84 mm), concentrations of E. coli were significantly lower than the mean (p < 0.0001). During the post-Niña period, with normal flows (Q = 14,900 m3 s(-1)) but with strong positive pluvial anomalies (A = +118 mm to +377 mm), the fecal indicator density reached maximum values (up to 2.699 log10cfu/100 ml, p < 0.0001). The multiple regression model used with all the results obtained in the Paraná River showed that variations in concentrations of E. coli are mainly explained by pluvial precipitations and hydrometric level (p = 0.001). Temporal patterns of concentrations of E. coli in a small, secondary course (Q = 101 m3 s(-1)) followed those of the Paraná River, but concentrations and peaks of E. coli produced by exceptional rains showed a higher magnitude (maximum: 3.325 log10cfu/100 ml). In the floodplain lakes, away from urban centers, concentrations of E. coli were not associated to hydroclimatic anomalies, but directly to vegetable cover: maximum concentrations were always registered during periods that lakes remained covered by floating macrophytes (mainly Eichhornia crassipes); on the contrary, minimum concentrations were registered during periods without vegetable cover.

Anaphylactic reaction to cinoxacin: report of one case associated with inferior acute myocardial infarction

Cinoxacin is an oral synthetic antibacterial agent, of the second generation quinolones group, with excellent efficacy in respiratory, intra-abdominal, pelvic, and skin and soft tissue infections. Overall, quinolones are well tolerated drugs, although phototoxicity and photoallergenicity is well demonstrated experimentally. In this report we show you a case of a man who presented a anaphylactic reaction associated with myocardial infarction, after taking a capsule of cinoxacin. We suppose that there is a direct participation of the heart in anaphylactic reactions, because acttivated mast-cells mediators can determine cardiovascular effects. Then performed double-blind placebo controlled challenge test with an alternative drug. We did not observe any adverse immediate or late adverse reaction to this drug.

[Prediction of the bacteriological quality of natural waters in urban environments. Effect of the El Niño-Southern Oscillation]

At the moment of examination, the bacteriological quality of water is not, to a large extent, more than an a posteriori evaluation: the population is advised afterwards that it had been exposed to a sanitary risk. The ideal situation for managing aquatic environments or recreational use would be to be able to predict at any moment their bacteriological quality. An approach would be to develop predictive models to relate the exceedance (number of days during which the bacteriological indicator exceeds the standards) with environmental variables. Studies were carried out at two beaches with different limnological characteristics, a fluvial beach and a lacustrine beach, from the beginning of 1998 to the end of 2000, so that it was possible to obtain information on the impact of very different hydroclimatic situations on microorganisms of sanitary interest (Escherichia coli and cyanobacteria). Three variables, maximum concentration of E. coli, rains and water level, justified 92.6% of the exceedance variance in the multiple regression model at the fluvial beach. Other abiotic variables (temperature, pH, conductivity, transparency and dissolved oxygen) showed collinearity problems or did not make statistically significant contributions to the model. During the El Niño event (gauge heights > 5 m) there were no exceedances after the rains, even with precipitations of 200 mm. Moreover, cyanobacteria density remained low (x = 1.191 +/- 0.703 log10 cian./ml). During the negative pluvial anomalies, although the exceedances of E. coli were not very frequent at both beaches due to the scarce rains, a massive development of cyanobacteria was produced (x = 4.657 +/- 0.578 log10 cian./ml) at the lacustrine beach. At this beach, the mean decay coefficient (K) for E. coli was significantly (p < 0.05) lower than that estimated for the fluvial beach (K = -0.682 +/- 0.32 versus K = -0.387 +/- 0.16, respectively), possibly due to the unfavourable environment created by the higher development of photosynthetic organisms. Analizing separately the anomalous period, variables that better explained (98.6%) the exceedances were (in addition to the maximum concentration of E. coli) pH, temperature and days without rains (DWR) before the sampling. The longest exceedances (6 to 8 days) were produced at the end of the negative pluvial anomalies, after prolonged periods (> 30 days) of droughts. Regression models obtained to predict the exceedance of E. coli were simplified using only three abiotic variables (water level, rains and DWR). Although, in this way, the percentage of explanation of the exceedance is lower (78.5%), the information needed for the model is obtained quickly and preventive measures can be carried out immediately while waiting for more information.

[Escherichia coli: diversity of biochemical phenotypes in aquatic environments (Santa, Fe, Argentina)]

During certain environmental conditions, the floating aquatic vegetation, mainly represented by Eichhornia crassipes (water hyacinth) invade and even cover water courses assigned to recreational activities or to the supply of drinkable water. The rhizosphere of these plants constitutes an unknown biotope of bacteria of sanitary interest, possibly different from waters without vegetation and of the sediment of the same aquatic system. To verify such possibility, 206 isolated strains in MacConkey Agar (Difco) were typified and identified (78 from water, 65 from sediment and 63 from rhizosphere) using the API 20 E system (v. 4.0) and Apilab plus software (v 3.3.3), both of bioMérieux (Marcy-l'Etoile, France, 1998). Nineteen different biochemical phenotypes from E. coli were found. The 79% of the population belonged to only 7 phenotypes; the 21% remaining, to the other 12 phenotypes. Twelve phenotypes did not share the biotopes, while only 4 were in the three. These results (and those obtained by other authors who used the API 20 E system in other biotopes) suggest that it would be possible to characterize the rhizosphere using those phenotypes that are found in smaller proportion. The greatest index of diversity (H) and evenness (E) were found in the rhizosphere (H = 2.903; E = 0.874). The dendrogram (average distances and UPGMA method) reaffirms the dissimilarity in biochemical phenotypes of E. coli populations of the rhizosphere with regard to the other biotopes. The most abundant bacterial species in the three biotopes were E. coli, Klebsiella terrigena and K. pneumoniae, corresponding to 75.2% of the community. The rhizosphere differed from Serratia odorifera and from Klebsiella spp. because of its higher rate of isolation.

[Temporal and spatial variations of coliforms and Escherichia coli in fluvial recreational waters (Salado River, Santa Fe, Argentina). Relationship with the quality standards]

There are no standards accepted by all the countries to fix top concentrations of microbiological indicators in recreational waters. Even now there is still a considerable discussion either in USA as in Europe. The universal application of a bacteriological quality criterion is hard due to several environmental factors that affect the relation between the indicator, the exposition and the health risks. Our purpose was to present a case study as an example of the influence of the climatic conditions in the application of the most known standards (Environmental Protection Agency of USA, Council of European Communities, World Organization of Health, and others from Canada, South Africa and Hong Kong). The pluvial rainfall increased the number of E. coli, thermotolerant coliforms (C Te), and total coliforms (CT) 6-10 fold, in comparison to the number registered during the steady-state conditions of the system. However, not all the standards included that factor. In Summer, hourly, daily and weekly variations were proved, therefore the standards that suggest fortnightly sampling frequencies would not be convenient in that system. Although the main source of variation was time, spatial variability was also detected. The percentage of E. coli among the C Te was very variable, but the average resulted low (26%) compared to the levels in temperate regions of other countries (> 90%). According to the directives proposed by the Commission of European Communities, the parameter has been changed (C Te for E. coli), but the standard has remained (2000/100 ml). Thus, the directive would be more permissive.

[Bacteriological quality of Bendetti Lake (Santo Tomé, Santa Fe Province, Argentina) and associated environmental variables]

The main objective was to determine the bacteriological quality of a shallow lake in the lower Salado River Basin (Bedetti, 31 degrees 40' S and 60 degrees 45' W). Seventy samples were tested by the most probable number (MPN) method, throughout three years. The number of thermotolerant coliforms was very variable: from 20 MPN/100 ml to 130,000 MPN/100 ml. These variations were mainly associated to the local rains (rs = 0.4853, p = 0.0001) and to the hydrometric level-h-(rs = 0.3835, p = 0.008). Statistically significant correlations between coliform bacteria and other variables (temperature, oxygen, pH, conductivity and transparency) were not found. The increase of coliforms associated to the increase of the hydrometric level indicates the presence of diffuse contamination sources. It was found that the rains affected the bacteriological quality, specially during the low water periods (h < 3.60). During the high water periods (h > 4.70) one of the main coliform contributor was represented by the incoming floating islans and aquatic macrophyte, from allochthonous fluvial systems. The coliform concentrations between the Bedetti lake and the Salado river were compared. The results show a better bacteriological quality of the lake (geometric average = 1,990/100 ml vs. 420/100 ml, n = 56) so that, connecting them by the construction of an artificial channel is not advisable.

[Frequency of vibrio cholerae isolation from water and plankton of the lower Salado river basin (Santa Fe, Argentina)]

In the lower Salado River Basin 85 samples of water and 40 of plankton were collected from January 1993 to December 1996. In the 69.4% of the water samples and in the 75% of the plankton samples Vibrio cholerae was detected. None of the isolate strains belonged to O1 and O139 serogroups. The seasonality in the frequency of isolation of V. cholerae tested by multiple proportions comparison test was not confirmed (p > 0.05). There were significant differences (p < 0.05) between the isolation frequencies found in the Salado River (85 samples, 69.4%) and those found in the Paraná River environments (16 samples, 25%) and in municipal waste effluents (18 samples, 33.3%).