Short communication: contribution of the immunovirological state and traditional cardiovascular risk factors to low HDL-cholesterol in HIV patients.

The prevalence of low HDL-C levels in an HIV population and its related factors was investigated. We undertook a multicenter, cross-sectional study of all HIV patients on regular follow-up in five hospitals (Southern Spain). A physical examination and fasting laboratory analysis were performed and a questionnaire about cardiovascular risk factors was provided. One thousand and seventy-two patients were included, 43.8% of whom had low HDL-C levels. The prevalence of low HDL-C was higher among patients diagnosed with AIDS, those not on antiretroviral therapy, those with a detectable HIV viral load, those with CD4 cell counts ≤350 cells/µl, smokers, and those with hypertriglyceridemia. For patients on antiretroviral therapy, the prevalence of low HDL-C was higher for those on protease inhibitors than those taking nonnucleoside reverse transcriptase inhibitors. In the multivariate analysis, low HDL-C levels were associated with tobacco use (OR 1.37, 95% CI 1.04-1.8; p = 0.04), hypertriglyceridemia (OR 2.94, 95% CI 2.2-3.8; p < 0.00001), CD4 cells count ≤350 cells/µl (OR 1.74, 95% CI 1.2-2.3; p < 0.0001), and a detectable HIV viral load (OR 1.85, 95% CI 1.3-2.5; p < 0.0001). The immunological and virological conditions, in addition to traditional cardiovascular risk factors such as tobacco use and hypertriglyceridemia, affect HDL-C levels in HIV-infected patients. For patients on antiretroviral therapy, the use of protease inhibitors is associated with a higher probability of low levels of HDL-C. Although it is not clear if the higher HDL-C levels associated with antiretroviral use are surrogates for decreased cardiovascular disease risk, this may be another reason to start antiretroviral therapy earlier.

[Analysis of the natural radioactivity due to the radon gas in the underground of Rome]. / Analisi della radioattività naturale dovuta al gas radon presente negli ambienti sotterranei della metropolitana di Roma.

BACKGROUND: Radon is a decay product of 238Uranium which is classified by WHO/IARC as group 1 carcinogen, given its causal relationship with lung neoplasia. An annual concentration of this gas higher than 500 Bq/m3 in workplace is considered potentially dangerous by the italian legislation. No data are currently available on radon level in underground tunnels, which are a potentially important source of exposure both for workers and travellers. MATERIAL AND METHODS: Measurements have been performed in a station and within the trains. Two months integrated measures, and 5 days continuous (hourly) assessments have been performed. Integrated measurements have been performed by means of 12 passive dosimeters, containing a detector made of CR39 (polymeric type), whereas active scintillation-type dosimeters have been employed for continuous assessments. RESULTS: Two months integrated measures: radon level in the station was 665 +/- 71 Bq/m3, whereas values within the trains ranged between 96 and 117 Bq/m3. Continuous measurements: Mean radon level during work activities was 783 +/- 536 Bq/m3 and thereafter it rose to 850 +/- 131 Bq/m3 CONCLUSIONS: Radon nelle levels in underground tunnels may exceed attention levels, whereas within trains they remain well below these levels. Further studies focused to assess the risk of underground employers are needed.

Platelet activation in patients with colorectal cancer.

Aspirin may reduce the risk of colorectal neoplasia at doses similar to those recommended for the prevention of cardiovascular disease. Thus, we aimed to address whether enhanced platelet activation, as assessed by the measurement of the urinary excretion of 11-dehydro-TXB(2) (a major enzymatic metabolite of TXB(2)), occurs in patients with colorectal cancer. In 10 patients with colorectal cancer, the urinary excretion of 11-dehydro-TXB(2) was significantly higher than in 10 controls, matched for sex, age and cardiovascular risk factors [1001(205-5571) versus 409(113-984) pg/mg creatinine, respectively, median (range), P<0.05]. The administration of aspirin 50 mg daily for 5 consecutive days to colorectal cancer patients caused a cumulative inhibition of platelet cyclooxygenase (COX)-1 activity either ex vivo, as assessed by the measurement of serum TXB(2) levels, or in vivo, as assessed by urinary 11-dehydro-TXB(2) excretion. In conclusion, enhanced platelet activation occurs in colorectal cancer patients. Permanent inactivation of platelet COX-1 by low-dose aspirin might restore anti-tumor reactivity.

Dissection of atrial septum after mitral valve replacement.

We report a patient who presented with paraprosthetic leak complicated by dissection of the interatrial septum after mitral valve replacement. A review of the literature provides confirmation that only 3 cases have been previously reported of this potential, albeit extremely rare, complication of prosthetic mitral valve replacement. Prosthesis oversizing and improper mitral annular handling appeared to be the predisposing factors of this complication.

L-5-hydroxytryptophan does not stimulate LH secretion directly from the pituitary in patients with gonadotrophin releasing hormone deficiency.

OBJECTIVE: There is abundant histological and physiological evidence that serotonin plays a role in the regulation of LH secretion in rats. Studies in human subjects have been few, but their results include the finding that pulsatile administration of L-5-hydroxytryptophan (5-HTP, the immediate precursor of serotonin) amplifies LH secretion in women in the medium-late follicular phase, and that this effect is not due to 5-HTP directly inducing LH secretion by the pituitary. We have investigated whether 5-HTP amplifies LH secretion by enhancing the response of the pituitary to GnRH. PATIENTS: Seven patients aged 20-40 years with hypogonadotrophic hypogonadism (HH) of hypothalamic origin (3 men with Kallmann's syndrome, 2 women without anosmia and with GH deficiency, and 2 women with anorexia nervosa). DESIGN: To prime the pituitary, subcutaneous pulsatile GnRH was administered for 7 days at the rate of one 5-20 micrograms pulse every 90 min. The day before the investigation, this regimen was replaced by 1.5-3 micrograms intravenous pulses at the same frequency. On the day of the investigation, 3 ml blood samples were taken every 10 min from 0850 to 19:00 hours. After the first two samples, the intravenous GnRH pulse frequency was increased to one per hour and was maintained at this level throughout the rest of the study. The first 4 h of the study acted as a control phase allowing determination of the pituitary response to GnRH. At 1300 h, 75 mg of the aromatic-L-amino-acid decarboxylase inhibitor carbidopa was administered orally; carbidopa does not cross the blood-brain barrier, and prevents peripheral conversion of 5-HTP to serotonin. At 1600 h, another 75 mg dose of carbidopa was administered, and administration of 8-20 mg pulses of 5-HTP at a rate of one pulse per hour was begun. MEASUREMENTS: LH was determined in triplicate by an immunoradiometric assay (IRMA), and LH pulses identified by means of a program developed in our laboratory. RESULTS: When pulsatile administration of GnRH was accompanied by administration of carbidopa and 5-HTP, LH pulse amplitude (2.32 +/- 0.71 IU/I) did not differ significantly from its value in either the GnRH+ carbidopa phase (2.58 +/- 1.12 IU/I) or the unaccompanied GnRH phase (2.77 +/- 1.76 IU/I). CONCLUSIONS: L-5-hydroxytryptophan-induced amplification of LH secretion in humans is not due to enhancement of the pituitary response to GnRH. The effect of L-5-hydroxytryptophan must therefore be due to its action on the hypothalamus, where it may be hypothesized that it increases GnRH release.

Reoperation for prosthetic thrombosis and acute neurologic injury.

Open-heart surgery in patients with recent cardiogenic embolic stroke represents a difficult management problem. We present a patient who developed thrombosis of a mitral tilting-disc prosthesis complicated by repeat cerebral embolic episodes that resulted in acute neurologic injury. We believe that in such patients the indication for reoperation must be individually evaluated but it is justified in young subjects, even in the presence of severe neurologic damage.

Long-term administration of pulsatile gonadotropin-releasing hormone for exploration of pituitary functionality in amenorrheic patients.

Differentiation between hypothalamic and pituitary amenorrhea is generally based on the luteinizing hormone-releasing hormone (LHRH) test (whether as a single dose, two consecutive doses, or pulsatile over 5-10 days), together with high-resolution imaging (computed tomography or magnetic resonance) of the sellar region. Long-term administration of gonadotropin-releasing hormone (GnRH) is generally used only for ovulation induction, and not for diagnostic purposes. Here, we report the results of long-term administration of GnRH to 19 women initially diagnosed as suffering from hypothalamic amenorrhea on the basis of LHRH testing and computed tomography imaging. During treatment, subjects received 20-micrograms pulses of GnRH every 90 min, subcutaneously from a portable infusion pump. Fourteen subjects responded (i.e. ovulated) during the first treatment cycle; one subject menstruated but did not ovulate during the first cycle, and the dropped out of the study; the remaining four subjects did not ovulate or menstruate despite at least three treatment cycles. Magnetic resonance imaging of the sellar region of these four subjects revealed pituitary lesions (partially empty sella in three cases, microadenoma in one case) which had not been detected by computed tomography. By contrast, no such abnormalities were detected in the nine responders who agreed to undergo magnetic resonance imaging. These findings suggest that long-term administration of GnRH is of value not only for ovulation induction but also for diagnostic purposes. Specifically, an initial diagnosis of hypothalamic amenorrhea is confirmed if there is a positive ovulation response after two GnRH treatment cycles; otherwise, pituitary amenorrhea should be suspected. Our results also suggest that magnetic resonance imaging is more effective than computed tomography for the detection of partially empty sella.

Tumor necrosis factor concentrations in hemolytic uremic syndrome patients and children with bloody diarrhea in Argentina.

Hemolytic uremic syndrome (HUS) is thought to be a vascular endothelial injury disease. The mechanism of injury is unknown although verocytotoxins (Shiga-like toxins (SLTs)) are known to be associated with it. Recent evidence suggests that in vitro treatment of some endothelial cells with tumor necrosis factor alpha (TNF-alpha) dramatically increases their susceptibility to SLTs. We studied 25 children with HUS, 63 children with SLT-positive bloody diarrhea, 62 children with bloody diarrhea not associated with SLTs and 39 children admitted for elective surgery, included as an age- and season-matched control group. The TNF-alpha concentrations were found to be significantly elevated in children with HUS (range, 1 to 95 pg/ml; geometric mean, 32.2 pg/ml) compared with the healthy controls (range, 0 to 53 pg/ml; mean, 12.5 pg/ml; P < 0.001). Because it is hypothesized that TNF-alpha elevation might precede development of HUS, we also studied children with blood diarrhea. The TNF-alpha serum concentrations were significantly higher during the first 10 days after onset of bloody diarrhea than after the first 10 days (P < 0.02). Such elevation could be associated with vascular endothelial glycolipid receptor up-regulation and increased susceptibility to the effects of SLTs.

Survival despite almost complete occlusion by chronic thrombosis of a Björk-Shiley mitral prosthesis.

We report a patient who was successfully reoperated because of almost complete thrombosis of a Björk-Shiley tilting disc mitral prosthesis. Considering the usually acute presentation and the frequently catastrophic consequences of most similar cases in the literature, the unusual feature of this case is that the patient survived until reoperation with minimal symptoms despite almost total prosthetic occlusion by a chronic thrombus.

Energy expenditure and gas exchange measurements in postoperative patients: thermodilution versus indirect calorimetry.

OBJECTIVE: To compare a method of measuring energy expenditure and gas exchange using the Fick principle with the standard indirect calorimetry technique. DESIGN: Prospective study of a consecutive sample of postoperative patients. Oxygen consumption (VO2), CO2 production (VCO2), respiratory quotient, and energy expenditure were derived from measurements of variables, including oxygen content and cardiac output. Energy expenditure and gas exchange were measured simultaneously by continuous indirect calorimetry over a 60-min period. SETTING: Surgical ICU in a university hospital. PATIENTS: Twenty-six consecutive patients (45 to 80 yrs) who underwent sustained surgical trauma. Excluded from the study entry were patients with time-related fluctuations of hemodynamic variables, poor cooperation, patients who required supplemental oxygen, or mechanical ventilation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: While the measurements of VO2 and VCO2 by calorimetry and thermodilution were significantly correlated with one another (for VO2, r2 = .93, p less than .001; for VCO2, r2 = .26, p less than .01), VO2 and VCO2 values by indirect calorimetry were consistently greater than VO2 and VCO2 values by the Fick method (p less than .01). The respiratory quotient calorimetric measurements ranged between 0.69 and 0.99, whereas the corresponding thermodilution measurements spread to impossible values, from 0.24 to 1.30 (0.821 +/- 0.07 vs. 0.740 +/- 0.24, p less than .05). There was an insignificant relationship (r2 = .06, p = .21) between the values of respiratory quotient by the two methods. A strong, positive correlation between energy expenditure measured by indirect calorimetry and energy expenditure measured by the Fick method was observed (r2 = .92, p less than .001). The limit of agreement between the two methods was -0.24 +/- 73 kcal/day/m2 (-1.00 +/- 305 kJ/day/m2). CONCLUSIONS: In postoperative patients, while VO2 and energy expenditure measurements by thermodilution are easy to perform and accurate for clinical purposes, VCO2, and respiratory quotient measurements are too imprecise and inaccurate to serve any useful function. Therefore, in those clinical situations in which an evaluation of respiratory quotient and substrate utilization may be useful for purposes of metabolic care of the surgical patient, precise measurements of gas exchange with indirect calorimetry are mandatory.

Immunoscintigraphy with 131I or 111In labelled OC 125 F(ab')2 fragments in patients with ovarian carcinoma.

To evaluate the clinical usefulness of immunoscintigraphy with OC 125 in ovarian carcinoma, we studied 25 patients suspected of having ovarian carcinoma or in follow-up after surgery. Fourteen patients were studied with 131I-OC 125 F(ab')2 and 11 with 111In-OC 125 F(ab')2. No differences were observed with the use of either radionuclide. Global diagnostic indexes obtained were S = 100%, Sp = 44,5% and A = 81%. The low specificity obtained was remarkable: 5 false positive results in two uterine myomas, one abscess, one follicular cyst and one granulation tissue scar. On the other hand, all lesions of ovarian carcinoma were detected. Analysis of the evolution of tumor/background (T/B) uptake ratios from the first to the second day of exploration revealed a tendency for the ratio to diminish significantly (greater than 15%) in false positive cases with the exception of the abscess while this did not happen in true positive cases, with the exception of a regional recurrence. Analysis of T/B ratio variations could contribute towards elevating the test's specificity.

Pefloxacin in the antibacterial treatment of immunodepressed patients.

Pefloxacin 800 to 1200 mg daily was given for 3 to 20 days, orally or intravenously, to 84 immunocompromised patients. Five patients dropped out because of side effects and 2 for other causes. Treatment efficacy was evaluated in 77 patients, 43 men and 34 women, aged 18 to 80 years. Immunodepression resulted from malignancy in 46 patients, LAS/ARC or AIDS in 28, and from unknown causes in 3. Fifty-eight patients had documented infections (respiratory-tract infections 29, urinary-tract infections 13, septicemia 10, other 6) and 19 had a fever of unknown origin (FUO). Cure or significant improvement of symptoms was achieved in 81% of patients with documented infections and in 74% of patients with FUO. Side effects (mainly gastrointestinal disturbances and skin rash) occurred in 7 patients (8.2%), including dropouts. These results suggest that pefloxacin may be useful for the antibacterial treatment of immunodepressed patients.

Chronic idiopathic hyperphosphatasia and fibrous dysplasia in the same child.

A generalized skeletal dysplasia with features of chronic idiopathic hyperphosphatasia and fibrous dysplasia of the mandible were observed in a 6-year-old child. The abnormal development of the bones resulted from enhanced remodeling and the failure of mature bone to form. The occurrence of the two lesions in the same child and a review of the literature support the hypothesis that pathogenesis of fibrous dysplasia and idiopathic hyperphosphatasia reflect an underlying common defect in the control of bone cell activity.

Congenital muscle fibre type disproportion: clinical, morphological and biochemical findings in children.

Muscle biopsies from quadriceps femoris muscle of normal subjects and subjects with symptoms of congenital myopathy, aged 1-3 years, were examined for morphological and biochemical differences. Four patients showed clinical signs of Congenital Fibre Type Disproportion (CFTD) as described originally by Brooke (1973), while the other cases showed only signs of hypotonia and diffuse weakness as described by Clancy et al. (1980). No morphological differences between patients with different clinical signs were found in any biopsy sample from the quadriceps femoris muscle, as regards fibre size; type I fibres were always smaller than type II fibres. The difference in fibre size was more than 15% in all cases, and the variability coefficient of the larger type II fibres was less than 250. Nevertheless, as regards fibre occurrence, two patients showed more type I fibres than type II fibres, four patients showed more type II fibres than type I fibres and one patient had a marked type II fibre predominance. Enzyme activities assayed in the crude mitochondrial fraction showed no abnormalities between normal subjects and patients. An increase in the activity of lactate dehydrogenase in the crude extract was found in all cases.

Acute effects of peritoneovenous shunt (Le Veen) on the hemodynamics and gas exchange in patients with hepatic intractable ascites.

The acute effects of the peritoneovenous shunt (LeVeen) on hemodynamics and pulmonary gas exchange in 6 consecutive patients with intractable ascites and cirrhosis were evaluated. After opening the peritoneovenous shunt, there was a marked increase in cardiac index, (from 3.78 +/- 0.4 to 5.86 +/- 0.4 1/min. m2, p less than 0.01), and mean pulmonary artery pressure (from 17.3 +/- 1.9 to 23.3 +/- 1.5 mmHg, p less than 0.05), while a significant decrease in systemic vascular resistances (from 1086 +/- 116 to 694 +/- 52 dynes.sec.cm-5, p less than 0.05) was observed. In all patients there was a drop in arterial oxygen tension (PaO2) (from 76 +/- 3 to 67 +/- 3 torr, p less than 0.01) and an increase in venous admixture (Qsp/Qt) from 13.1 +/- 2 to 18.9 +/- 2%, p less than 0.01). The comparable increase in cardiac output and in venous admixture produced by opening the peritoneovenous shunt, might be related to the massive transfusion of ascitic fluid into the intravascular compartment. It is therefore concluded that this impairment of tas exchange further support discarding an appropriate amount of ascitic fluid at the time of shunt insertion.

A family with the Saethre-Chotzen syndrome.

Acrocephalosyndactyly (ACS) is an inherited syndrome of premature synostosis of the cranial sutures and abnormalities in the distal segments of the limbs. Several forms of ACS have been described. ACS type III (or Saethre-Chotzen syndrome) is characterized by microcephaly, skull asymmetry, mild syndactyly, and facial abnormalities. We describe an Italian family with ACS III in which two sibs are clearly affected; the mother and the maternal grandmother show some features of the syndrome.