Use of bone allograft in tibial plateau fractures

To determine the behaviour of bone allografts in the treatment of tibial plateau fractures, 20 recipients of frozen bone allograft for a depressed tibial plateau fracture were studied. Incorporation of grafts took place in all cases, and no complication secondary to the allograft use has been detected. To avoid donor site morbidity associated with harvesting iliac crest, the use of frozen bone allograft is a good alternative in the treatment of depressed tibial plateau fractures.

Proportional morbidity rates of enteropathogens among diarrheic dairy calves in central Spain

Faecal samples from 218 diarrheic dairy calves in 65 dairy herds, selected by convenience, were screened for the presence of rotavirus, coronavirus, Cryptosporidium spp., F5+ Escherichia coli and Salmonella spp. Animals surveyed were from 1 to 30 days old. Cryptosporidium and rotavirus were the most commonly detected agents (52.3% and 42.7% of the samples positive, respectively). F5+ E. coli was detected in the faeces of 11.9% of the calves and bovine coronavirus was detected in the faeces of 7.3% of the calves. Salmonella spp. was only found in the faeces of two calves (0.9%). Mixed infections with two or more agents occurred in 28% of the calves. Concurrent infection of rotavirus and Cryptosporidium was found in 21.6% of the calves. Two tests were used for the detection of rotavirus (a commercial ELISA and PAGE), F5+ E. coli (ELISA and bacterial culture) and Cryptosporidium (ELISA and microscopy). The validity of the commercial ELISA for the detection of rotavirus, F5+ E. coli and Cryptosporidium in faeces from diarrheic calves was evaluated using PAGE, bacterial culture and microscopy as gold standard, respectively. The ELISA showed a very low sensitivity (28.6%) for the detection of F5+ E. coli compared to bacterial culture.

[Nutritional evaluation of children with respiratory failure (RF): anthropometric evaluation upon admission to the pediatric intensive care units]

OBJECTIVE

Protein-energy malnutrition (PEM) constitutes an important complication in children submitted to intensive care treatment for respiratory failure (RF). This complication is not usually evaluated in assessment protocols. Nutrition assessment in a Pediatric Intensive Care Unit (PICU) was performed in children with respiratory failure.

PATIENTS AND METHODS

A prospective study involving 65 children (1-158 months of age) with RF at admission to the PICU was carried out. The patients studied were divided into four groups according to their etiology: Group I (n = 29) included those with acute bronchial pathology; Group II (n = 17) those with pneumonia: Group III (n = 11) those in the post-operative period following cardiac surgery; and Group IV (n = 8) those patients with multiple-organ dysfunction. All patients in Groups I, II, and III had chronic diseases. Anthropometrical and nutritional evaluation included weight, height and body mass index (w/h2).

RESULTS

The weight for age was low (59%). Height deficit was observed in a significantly lower percentage of the patients (13.1%). The body mass index showed values in relationship to the 50th percentile that varied between 83.4 +/- 23.1% and 97.1 +/- 4.7%. In 68.9% of the patients the criteria of global malnutrition were met according to the classification of McLaren and Read.

CONCLUSIONS

The data confirm that PEM is frequent in patients with RF in the PICU and emphasize the usefulness of anthropometrical evaluation as an important, simple and non-invasive method of nutritional evaluation. Early and intensive nutritional intervention can reduce or prevent the vicious circle of malnutrition in RF patients hospitalized in the PICU.

[Hemangioma of the spermatic cord. Presentation of a case with review of the literature]

OBJECTIVE

To describe a rare variety of spermatic cord tumor, with special reference to the differential diagnosis. The literature is briefly reviewed.

METHODS

The clinical and pathological features of a tumor located in the right inguino-scrotal region of a 27-year-old male patient are described.

RESULTS

The preoperative evaluation disclosed an irregular mass in the right hemiscrotum that was unconnected to the testis. The patient underwent orchidectomy and resection of the tumor. Pathological analysis of the surgical specimen revealed a hemangioma of the spermatic cord.

CONCLUSIONS

Hemangioma of the spermatic cord is a very uncommon tumor, it is a slow growing, indolent, benign scrotal lesion that must be distinguished from other paratesticular masses or tumors with similar clinical features. Ultrasound and other diagnostic imaging techniques are not useful in making the preoperative differential diagnosis.

Infection and associated risk factors in the immediate postoperative period of pediatric liver transplantation: a study of 176 transplants

OBJECTIVE

To describe the characteristics of infections occurring in the immediate postoperative period of orthotopic liver transplantation (OLT) in children in a pediatric intensive care unit (PICU) and the associated risk factors.

DESIGN

Retrospective cohort study.

SETTING

Multidisciplinary 16-bed pediatric intensive care unit in a tertiary university hospital.

PATIENTS

One hundred and thirty-three pediatric patients (range 6M to 22 yr) who underwent 176 liver transplantations and were admitted to the pediatric intensive care unit for at least 48 h.

RESULTS

A total of 180 infectious episodes (IE) occurred in 78 (59%) patients who underwent 96 (54.5%) liver transplantations (1.35 IE/patient; 1.02 IE/transplantation). The mean stay was 15.4 +/- 1.1 d (mean +/- SD) and 22 patients died in the pediatric intensive care unit. One hundred and thirty-one IE (72.8%) were bacterial, 31 (17.2%) fungal, and 14 (7.8%) mixed bacterial and fungal. 39% of the IE appeared in the first postoperative week and 27% in the second postoperative week. The most common sites of infection were abdomen (48.3%) and blood stream (26.1%). Bacteria, alone or with fungi, were present in 145 IE (1.1 IE/patient). Gram-positive aerobic bacteria (63%) predominated over gram-negative bacteria (54%) and fungi. Fungi were present in 45 IE; 53.4% of the infections occurred in lung (73% yeasts). The risk factors for infection that were identified were related with younger age, lower body weight, longer cold ischemia time, partial graft, and the volume of packed red blood cell transfusions. Infected patients had more postoperative complications and longer stay in the PICU (21 +/- 16 vs. 8 +/- 6 d), but no increase in mortality. The risk of infection increased 2.38 times with partial grafts and 1.1 times with each intraoperative transfusion of 20 ml/kg of packed red blood cells (RBC).

CONCLUSIONS

Infection in the immediate postoperative period of pediatric OLT was related with a high morbidity but was not related significantly with increased mortality. The main risk factors for infection in the postoperative period of OLT were related essentially with small recipient size and the inherent complexity of the operation. Routine oropharyngeal decontamination is recommended, as well as early administration of oral nystatin in preoperative intestinal decontamination. The risk of infection increased 2.38 times with partial grafts and 1.1 times with the transfusion of every 20 ml of packed RBC.

The ideal therapy must be defined in each geographical area: experience with a quadruple therapy in Spain

BACKGROUND

Multiple therapeutic combinations have been tested to determine the optimal regimen(s) for Helicobacter pylori eradication, leading to very different results depending on the geographical area. Our goal was to evaluate the efficacy of a "quadruple" therapy with omeprazole, tetracycline, bismuth and metronidazole in our area.

MATERIALS AND METHODS

We investigate 106 consecutive patients with active peptic ulcer disease (duodenal, gastric or both) and Helicobacter pylori infection. One-week therapy with omeprazole 20 mg b.i.d., tetracycline hydrochloride 500 mg q.i.d., colloidal bismuth subcitrate 120 mg q.i.d., and metronidazole 250 mg t.i.d was prescribed. Between the days 30 and 40 after treatment ended follow-up endoscopy was performed. Eradication was defined as both negative urease test and histology. Between days 90 and 360 a 13C urea breath test was performed in 100 patients.

RESULTS

Of the 106 patients in the study, 91 had duodenal ulcer, 12 had gastric ulcer, and 3 had both. Side effects were observed in 25% of the cases. Eradication was achieved in 87.7% (93/106; CI 79.9-93.3). Healing was obtained in 95.2% (100/105; CI 89.2-98.4); 97.8% (CI 92.4-99.7) in those eradicated and 75% (CI 42.8-94.5) in non-eradicated (p < .01).

CONCLUSIONS

Quadruple therapy with omeprazole, tetracycline, bismuth subcitrate and metronidazole achieves healing rates up to 95-100%. The 87.7% eradication rate obtained suggests that the regimen we used is a reasonable therapeutic alternative in our area.

Non-conventional yeasts as hosts for heterologous protein production

Yeasts are an attractive group of lower eukaryotic microorganisms, some of which are used in several industrial processes that include brewing, baking and the production of a variety of biochemical compounds. More recently, yeasts have been developed as host organisms for the production of foreign (heterologous) proteins. Saccharomyces cerevisiae has usually been the yeast of choice, but an increasing number of alternative non-Saccharomyces yeasts has now become accessible for modern molecular genetics techniques. Some of them exhibit certain favourable traits such as high-level secretion or very strong and tightly regulated promoters, offering significant advantages over traditional bakers' yeast. In the present work, the current status of Kluyveromyces lactis, Yarrowia lipolytica, Hansenula polymorpha and Pichia pastoris (the best-known alternative yeast systems) is reviewed. The advantages and limitations of these systems are discussed in relation to S. cerevisiae.

Parathyroid function in long-term renal transplant patients: importance of pre-transplant PTH concentrations

Lack of resolution of hyperparathyroidism after long-term renal transplantation is common. The relative roles of the graft function attained and the degree of pre-transplant hyperparathyroidism have not been established. Intact parathyroid hormone (iPTH) and several clinical parameters were studied before and 68.6+/-26.8 months (range: 30-124) after renal transplantation in 62 patients (20 females/42 males) with good renal function (creatinine <2 mg/dl). iPTH decreased from 214+/-229 pre-transplantation to 116+/-70 pg/ml post-transplantation (P<0.01). However, only 22.6% of patients had PTH concentrations in the normal range, and values greater than twice the upper normal limit were not uncommon (27.4%). Of the many variables analysed, creatinine (r=0.43; P=0.001) and pre-transplant PTH (r=0.31; P=0.02) significantly correlated with post-transplant PTH. After selecting patients with serum creatinine <1.5 mg/dl (n=46), pre-transplant PTH emerged as the more important predictor of post-transplant PTH (r=0.58; P<0.0001). After controlling for creatinine, the partial correlation was r=0.53, P<0.0001. We concluded that spontaneous resolution of hyperparathyroidism after renal transplantation is uncommon. In addition, the magnitude of pre-transplant hyperparathyroidism and the renal function determine the long-term post-transplant parathyroid function.

[Drug inhalation therapy. Therapy for patients with respiratory disorders]

We detected a high number of patients suffering from respiratory ailments which require successive hospital stays due to acute setbacks in their chronic respiratory ailments. The majority of these patients receive outpatient clinic treatment based on use of an inhaler. Given the direct relationship between the correct use of an inhaler and its effectiveness, we designed our project with the goal to discover the adroitness these patients have with an inhaler. The results of our study showed that 67% of the patients tested did not correctly use their inhaler, there by annulling or diminished the effectiveness of its use.

A clinical, pharmacologic, and polysomnographic study of sleep benefit in Parkinson's disease

We assessed the effect of sleep benefit on motor performance in Parkinson's disease (PD) and analyzed its relation to pharmacologic and sleep measures. The sleep benefit phenomenon-motor improvement after sleep before drug intake-in patients with PD has been addressed by questionnaire studies, but objective data are scarce. Ten PD patients with sleep benefit were pairwisely matched to 10 PD patients without sleep benefit for gender, age, PD symptom duration, and medications. We examined motor performance at night before sleep, during morning baseline state immediately after spontaneous awakening, and continuously after intake of the usual levodopa dose. Plasma levodopa concentrations were measured serially and all-night polysomnography was performed. Between night and morning evaluations, motor state improved slightly in patients with sleep benefit and deteriorated slightly in patients without sleep benefit. The difference between both groups proved to be significant. After levodopa induced "on" state, patients with sleep benefit had more severe interdose "off" than those without. Levodopa concentrations and polysomnographic findings were similar in both conditions, although there was a trend toward more abnormal sleep measures in sleep benefit patients. Sleep benefit is a small but significant phenomenon. It does not clearly relate to a specific sleep variable; however, patients with sleep benefit showed a different response profile to levodopa. Subjective perception or possibly sensory mechanisms could play an additional role in sleep benefit in PD.

Reference values of gastric intramucosal pH in children

To determine the reference values of gastric intramucosal pH (pHi) by tonometry in paediatric patients, we studied 17 children (nine males, eight females) with no systemic or gastrointestinal disease, aged six months to 12 years undergoing minor reconstructive surgery. Following anaesthetic induction a sigmoid tonometry catheter was inserted (Tonometrics, Inc.) into the stomach of the patients under direct vision. All children were normoventilated and were haemodynamically stable. After an equilibration period of 30 min, gastric pHi was calculated by applying the Henderson-Hasselbalch equation on the PCO2 obtained with the tonometer and the bicarbonate from the arterial blood gas analysis. The mean gastric pHi in our patients was 7.35 +/- 0.06 (SD). The normal pHi in the general population is estimated to be 7.31-7.40, with a confidence interval of 99%. No correlation was found between pHi and arterial pH, bicarbonate or base excess. Under conditions of normal ventilation and haemodynamic stability, healthy children during general anaesthesia have gastric intramucosal values similar to those of adults.

[Trends in human immunodeficiency virus infection prevalence in homosexual/bisexual men in Madrid (1986-1995)]

BACKGROUND

We analysed the trend in seroprevalence for human immunodeficiency virus (HIV) in homosexual or bisexual men who voluntary requested the test in a sexually transmitted disease/HIV clinic in Madrid.

PATIENTS AND METHODS

We studied 5,424 homo/bisexual non-injecting drug user (non-IDU) men, who came for the first time since 1986 to 1995. We analysed the HIV seroprevalence taken into account the year, age and exchange of sex by money. A hundred and thirty-six IDU homo/bisexual men were also attended during the same period and they were compared with non-IDU.

RESULTS

HIV seroprevalence among the 5,424 non-IDU homo/bisexual men were 20.2%, rising from 19.6% in 1986 to 29.6% in 1990. After then, the trend decreased to 15.3% in 1995 (chi 2 for trend, 66.8; p < 0.0001). Average age was three years higher among seropositives (p < 0.0001), and showed an upward trend from 29.9 in 1986 to 34.6 in 1995 (p = 0.0059). Seroprevalence among homosexuals younger than 25 fell in the last years. One percent of individuals had ever practiced the prostitution. They were younger (average age, 27.6), and their HIV seroprevalence were 25.9%. A hundred and thirty-six IDU homo/bisexual men were also attended for the first time, being 2.4% of overall homo/bisexual men. They had a higher seroprevalence (48.5%) than non-IDU (p < 0.0001), and did not show any significative time-trend.

CONCLUSIONS

A favourable evolution can be observed in HIV seroprevalence among homo/bisexual from Madrid, Spain, men who came to be tested, especially among the youngest. Prevention programs should make an effort to maintain this trend.

[The impact of HIV infection on the incidence of syphilis and gonorrhea at a university hospital (1985-1994)]

Syphilis and gonorrhea are two sexually transmitted diseases (STD) which still persist in spite of the existence of effective treatment. In this paper the incidence of these two diseases was evaluated between 1985-1994, a decade during which the problem of HIV infection arose. Every patient who attended the STD Program at the Hospital and was suspected of having syphilis and/or gonorrhea was clinically evaluated and was subjected to the following tests: a) search for Neisseria gonorrhoeae (Ng) and penicinilase producers (PPNG) identification, b) search for Treponema pallidum (Tp) by darkfield microscopy, c) serological studies for syphilis. From 1985 to 1991 the average of positive cases for Ng was 14.8% while from 1992 to 1994 it was 4.0% (p < 0.0001) showing a dramatic decrease between 1991 and 1992. PPNG increased from 8.7% in 1985 to 44.6% in 1988 and then slowly decreased down to 26.9% in 1994. From 1985 to 1990 the average of positive darkfield examinations was 20.7% while from 1991 to 1994 it was 12.2% (p < 0.0001). Between 1985 to 1988 syphilis serological studies showed 45.7% positive cases dropping to 34.3% between 1989 and 1994 (p < 0.0001). HIV infection appearance had a wide repercussion throughout the world generating behavioral and sexual habit changes which have probably helped to prevent these two STD. Gonorrhea incidence was also influenced by the appearance of new effective treatments, even against PPNG, such as fluorated quinolones and third generation cephalosporines. The population studied belongs to the most crowded area in Argentina, so that these observations should not be extrapolated to the rest of the country.

Visceral leishmaniasis diagnosed by colonoscopy

Zoonotic visceral leishmaniasis is common in western Mediterranean countries. A strong link between visceral leishmaniasis and human immunodeficiency virus (coinfection) has been proved, especially in Spain, which is an endemic area. This suggests that Leishmania may behave opportunistically. We report a case of colonic leishmaniasis in a 23-year-old Spanish woman infected with the human immunodeficiency virus.

[Sclerosing hepatocarcinoma not associated with hypercalcemia]

The sclerosing hepatocellular carcinoma is an unusual subtype of hepatocellular carcinoma characterized by an intense fibrous stroma in which the tubular structures are embedded. Histological diagnosis is difficult, and misinterpretation as cholangiocarcinoma or metastatic adenocarcinomas may occur. It usually presents on non-cirrhotic livers. Metastases located outside of the liver are frequent as well as hypercalcemia and low levels of serum phosphate. We report a case of this rare histopathologic subtype of hepatocellular carcinoma in a 35-year-old woman, asymptomatic and with no previous history of chronic liver disease. It was detected by a routine gynaecological ultrasonography. An important increase of serum alpha-fetoprotein was noted. Extension studies showed bilateral lung metastases. Several palliative therapies were tried out, including epirrubicin, with partial response. Twenty months after the diagnosis the patient's situation is nearly terminal.

The ornithine decarboxylase gene from Candida albicans. Sequence analysis and expression during dimorphism

The gene (CaODC) coding for ornithine decarboxylase, a key enzyme in polyamine biosynthesis, was cloned from Candida albicans by PCR and characterized. The deduced protein contains 470 amino acids together with the substrate- and co-factor-binding sequences which define the ornithine decarboxylases of eukaryotic species. It shows a high homology with other ODCs, mainly those from Saccharomyces cerevisiae and Neurospora crassa. A putative PEST sequence, which correlates quite well with those described for other fungal ODCs, could be identified in the protein. The mRNA of the gene is 2.4 kb in size and by primer extension a long leader sequence was found at -558 bases upstream of the predicted start of translation. An identical single ODC gene was identified in three different C. albicans strains. During the dimorphic switch, a transient initial increase in ODC activity was observed. This increase was not accompanied by a rise in the levels of the transcript, suggesting that ODC activity levels may be regulated post-transcriptionally during differentiation.

[Factors related to the appearance of peripheral vascular complications after taneous cardiovascular interventions]

BACKGROUND

Percutaneous diagnostic and therapeutic cardiac catheterization procedures carries some risks, most of them related to the appearance of peripheral vascular complications. These complications imply additional treatments for the patient including vascular surgery, longer hospital stays and increased costs. Some clinical and procedural variables have been pointed out as independent predictors of appearance of vascular complications. Nevertheless, no information have been reported concerning to the influence of the experience of the cardiologist who performs the procedure or provides the local hemostasia and the rate of vascular complications.

OBJECTIVE

To characterise the type and incidence of peripheral vascular complications in patients undergoing a percutaneous cardiac procedure, to identify the predictors and to determine the influence of the professional experience and the complexity of the technique in the complications rate.

METHODS AND RESULTS

Within 1-year (1994 to 1995) period, 1,008 consecutive patients undergoing a percutaneous cardiovascular procedure (750 diagnostic and 258 therapeutic) were prospectively included. Seventy percent were male. Mean age was 63 +/- 2 years. A total of 55 vascular complications were demonstrated (5.6%): 36 (3.6%) hematomas, 14 (1.4%) pseudoaneurysms, 2 (0.2%) arteriovenous fistula, 2 (0.2%) episodes of limb ischemia and 1 (0.1%) retroperitoneal hematoma. Only 28 (2.8%) were severe complications. By multivariate analysis, only experience to perform hemostasis (OR: 3.36; 95% CI: 1.37-8.22), previous treatment with aspirin (OR: 2.69; 95% IC: 1.31-5.52), left femoral artery puncture (OR: 2.53; 95% IC: 1-1.02), sheath removal later than 60 minutes (OR: 1.02; 95% IC: 1.01-1.04) and hemostasis which lasted > 30 minutes (OR: 1.01; 95% IC: 1-1.02), were independent predictors of vascular complications.

CONCLUSIONS

Vascular complications rate after percutaneous cardiovascular procedures was low. Most of them associated to procedural variables and potentially avoidable, with promotion of a well planned policy of training in order to modify the factors involved.

Chemical basis of the resistance of barley seeds to pathogenic fungi

The 5-(n)-alkylresorcinol fraction of the epicuticular waxes of Hordeum vulgare seeds appeared to be responsible for their in-born resistance to pathogenic fungi such as Aspergillus niger and Penicillium crysogenum. The antifungal properties of this fraction were evaluated qualitatively and quantitatively with a novel bioassay where the extreme lipophilicity of these compounds was taken into account. The minimum inhibitory concentration in the fungi tested ranged from 5.6 to 10 micrograms cm-2 for the alkyresorcinols. The behaviour of the different cultivars against these fungi could be predicted by measuring the natural amount of resorcinols of each variety by TLC-scanning densitometry. The ranking of cultivars thus established correlated well with the field behaviour of each cultivar, providing a useful and rapid method for predicting the behaviour against fungi of new varieties being developed.

Analysis of costs in a pediatric ICU

OBJECTIVE

To analyze the actual cost of pediatric intensive care and its different components, particularly the differences between various patient groups, with special reference to the variable cost and the elements included in it.

DESIGN

Prospective, observational study.

SETTING

Multidisciplinary 12-bed pediatric intensive care unit (PICU) in a tertiary university hospital.

PATIENTS

495 admissions to the unit over 17 consecutive months; 64.2% were medical patients and 35.8% were surgical patients; the mean (SE) stay in the PICU was 6.6 +/- 0.4 days.

MEASUREMENTS AND RESULTS

The fixed cost per day per patient was calculated, including the costs of physicians, nurses, auxiliary and other personnel who worked during the study period, and the costs of structural depreciation, maintenance, consumption, and disposable material. The variable cost was individually calculated from the costs of routine procedures and also included expenditure on pharmaceuticals, blood products, biochemical, hematological, and bacteriologic tests, radiology, image diagnosis procedures, and other procedures. The Physiologic Stability Index (PSI) was obtained in the first 24 h after admission. The mean fixed cost per patient per day was u.s. $608, which represents 72% of the total patient cost during this study; 86% of this amount was for personnel (58% for nurses and auxiliary staff). Variable costs came to 28% of the total amount, and were $218 +/- 100 (M +/- SEM) per patient per day. In addition to the costs of their longer stay in the PICU, the daily variable costs of nonsurvivors were higher than those of survivors ($542 +/- 52 vs $179 +/- 7; p < 0.001). We classified the patients into four groups according to their PSI score in the first 24 h; variable daily costs increased (p < 0.05) in all comparisons with the PSI level: group I: < 4 points ($155 +/- 0.5), group II: 5-9 points ($210 +/- 13), group III: 10-14 points ($324 +/- 54), group IV: > 15 points ($480 +/- 42). However, this pattern was not found for all resources: the cost of treatment techniques and biochemical and hematological tests increased, but the consumption of antibiotics, parenteral nutrition, blood products, and bacteriologic tests reached their maximum level in groups I-III and radiology was not significantly influenced by PSI level.

CONCLUSIONS

The cost of personnel was the biggest factor in intensive care costs: 62.4% of the total costs. Nonsurvivors generated 3 times the mean variable daily expenditure on survivors and had longer stays in the PICU. The increase in PSI score on the first day was associated with a global increase in variable costs. The cost of treatment techniques significantly increased as the illness became more severe but consumption of antibiotics and parenteral nutrition and use of bacteriologic tests and radiology did not.

Unusual locations of osteoarticular tuberculosis

Tuberculosis continues to occur frequently in some underdeveloped regions. Bone and joint tuberculosis is less common than the pulmonary form. Fourteen cases of bone and joint tuberculosis in unusual locations are presented. Tuberculostatic treatment and surgical approach were associated in all the patients. In 6 cases an arthrodesis of the affected joint was carried out. A surgical debridement was done in 6 patients and a needle biopsy in 2 patients in order to obtain samples for pathology and bacteriology. Twelve of the 14 patients recovered. One patient who was affected by atlanto-axial tuberculosis died within the immediate postoperative period. A second one affected by the acquired immunodefiency syndrome died 4 months after surgery.

[Rapid and slow progression of the infection by the type 1 human immunodeficiency virus in a population of seropositive subjects in Madrid]

BACKGROUND

The rate of progression to AIDS in HIV-1 infected subjects is variable, and circumstances associated with more rapid or slow development of severe immunodeficiency might be grouped in three categories; environmental cofactors, host features, and particular virulence of the virus itself. Currently, it is not yet clear the the relative impact of each one.

PATIENTS AND METHODS

A cross-sectional study was done in a cohort of 1,783 IV-1 infected persons from three centers located in Madrid, mainly devoted to attend persons at risks for HIV infection. Long-term nonprogressors (LTNP) were defined as those with more than 8 years of confirmed HIV seropositivity, and CD4+ T-cell count above 500 x 10(6)/I in the absence of antiretroviral therapy or symptoms suggesting immunodeficiency. Rapid progressors (RP) were those with less than 5 years from seroconversion and repeatedly current CD4+ T-cell count below 200 x 10(6)/I. An analysis of different epidemiological, immunological and virological features was performed comparing LTNP and RP.

RESULTS

Among 1,783 HIV (+) subjects studied, 100 (5.6%) fulfilled criteria for LTNP and 12 (0.7%) for RP. Among LTNP, stabilized CD4 slope was seen in 16 (33%) out of 48 after more than 8 years of infection. Variables statistically associated with LTNP were: past history of intravenous drug addiction (80% of them), male gender (79% of them), high alcohol intake (48% of them), HIV-1 non-syncitium inducing viral phenotype, and very low or undetectable HIV-1 plasma viremia. In contrast, variables associated with RP were: infection by sexual contact (75% of cases), female gender (50% of them), syncitium-inducing viral plenotype, and high titers of plasma viremia. The CD4/CD8 ratio below 1 was seen in all RP and in 88% of LTNP. However, a preferent depletion of CD4+ cell occurred in the first group, instead of an enhancement of the CD8 T-cell count in LTNP. The prevalence of serological markers for hepatotropic viruses and other potential infectious cofactors was not higher in RP.

CONCLUSIONS

Multiple factors seems to account for the different rate of disease progression observed in HIV-1 infected persons. The dynamic equilibrium between the immune system and the virulence of the virus seem to be influenced--but not determined--by environmental infectious or non infectious cofactors.

Influence of age of the donor sheep on the phagocytosis of Staphylococcus aureus subspecies anaerobius and S aureus by neutrophils

The age of the sheep donating neutrophils had a marked influence in vitro on their phagocytic ability with respect to Staphylococcus aureus and S aureus subspecies anaerobius. Neutrophils from lambs five to eight weeks old phagocytosed these organisms significantly less efficiently (P < 0.001) than neutrophils from adults two to four years old. However, neutrophils from the young animals phagocytosed S aureus significantly (P < 0.001) better than S aureus subspecies anaerobius (61.5 v 53.8 per cent), whereas there was no significant difference in the ability of the neutrophils from adult sheep to phagocytose S aureus and S aureus subspecies anaerobius (68.2 v 68.2 per cent).