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M Roca

Publications and source records attributed to M Roca.

At least 37 records · Page 2Linked to original sources
PubMed2000

Littoral cell angioma with severe thrombocytopenia.

Littoral cell angioma (LCA) is a recently described splenic vascular tumor. We present a new case in a 62-year-old woman with severe thrombocytopenia and mild bleeding diathesis, but without palpable splenomegaly. Abdominal ultrasound and magnetic resonance showed multiple nodular images, suggesting splenic hemangiomas. A platelet kinetic study revealed a very short platelet survival. As the spleen was the site of platelet destruction, splenectomy was carried out. Histopathological and immunohistochemical data allowed a final diagnosis of LCA. Following splenectomy, the patient showed a transitory normalization of the platelet counts. Thrombocytopenia then reappeared but was moderate, without hemorrhagic diathesis. A second platelet kinetic study, performed 16 months post-splenectomy, showed hepatic platelet destruction. However, there were no macroscopic hepatic lesions in a second abdominal magnetic resonance study. This case illustrates the difficulties involved in determining the etiology of many peripheral thrombocytopenias.

Female↗
PubMed2000

Cyclical etidronate versus sodium fluoride in established postmenopausal osteoporosis: a randomized 3 year trial.

To compare the effects of sodium fluoride and etidronate in severe postmenopausal osteoporosis, we conducted a 3 year, prospective, trial in 118 postmenopausal osteoporotic women with at least one vertebral fracture, who were randomly assigned to receive sodium fluoride (25 mg twice daily, as enteric-coated tablets) plus calcium (1000 mg/day) or intermittent etidronate (400 mg/day for 14 days) followed by calcium (1000 mg/day for 76 days). Lateral spine X-ray films and dual-energy X-ray absorptiometry (DXA) measurements of the lumbar spine and proximal femur were performed at enrollment and yearly. Nonvertebral fractures were recorded every 6 months. Thirty-one women in the fluoride group and 47 in the etidronate group completed the trial. At 36 months, the mean change from baseline of the lumbar bone density in the fluoride group was 8.5 +/- 2.04% (p = 0.001) and in the etidronate group was of 3.6 +/- 0. 84% (p < 0.001). The changes in the fluoride group were significantly higher than in the etidronate group (p = 0.01). Both groups showed nonsignificant changes in femoral neck bone density. There was no significant difference between groups in the cumulative proportion of women with new vertebral fractures, with an incidence in the fluoride group of 16% vs. 17% in the etidronate group. However, the number of new vertebral fractures was significantly lower in the fluoride group (6 fractures) than in the etidronate group (19 fractures) (p = 0.05). The number of patients with nonvertebral fractures was similar in both groups. A high incidence of side effects, mainly gastrointestinal symptoms and lower extremity pain syndrome, was observed in the fluoride group. Etidronate was well tolerated. We conclude that, in women with severe osteoporosis, although sodium fluoride is more favorable than cyclical etidronate for increasing lumbar bone mass, no differences were observed in the incidence of fractures.

Administration, Oral↗
PubMed2000

Allelic variants of the thiopurine S-methyltransferase deficiency in patients with ulcerative colitis and in healthy controls.

OBJECTIVE: Thiopurine S-methyltransferase (TPMT) is a cytosolic enzyme that catalyzes the inactivation of mercaptopurine, azathioprine, and thioguanine. The genetic polymorphisms in the TPMT gene that regulate TPMT activity are inherited as an autosomal recessive trait and patients with genetically determined low levels of TPMT activity develop severe myelosuppression when treated with standard doses of the above-mentioned drugs. We have analyzed the frequencies of the allelic variants of the TPMT gene in a white European population of healthy blood donors from Spain and The Netherlands, and in a group of patients suffering from ulcerative colitis (UC) with a similar genetic background. METHODS: Two hundred and thirteen unrelated healthy individuals (HC) and 146 UC patients were typed for the polymorphic sites at positions 460 (G-->A) and 719 (A-->G) of the TPMT gene using specific polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) methods. RESULTS: There were no significant differences between the allele frequencies observed in the group of UC patients and those of the control group (10% of cases were heterozygous carriers of a TPMT mutant allele). The most frequent mutant allele in both UC and HC groups was TPMT3A (A460-->G719) (60% of carriers). TPMT3B (A460-->A719) and TPMT3C (G460-->G719) alleles were more often found in our study than in previously reported studies, reflecting the different genetic backgrounds of the European populations analyzed. CONCLUSIONS: Genotyping methods provide a simple and reliable screening to identify patients with a high risk of developing severe bone marrow toxicity if treated with thiopurine drugs. In UC patients, TPMT genotype should be determined before the initiation of azathioprine therapy.

Alleles↗
PubMed2000

[Labelling of ceftizoxime with 99mTc].

AIM OF THE STUDY: A new method to label antibiotics with 99mTc, using a third generation, wide spectrum cephalosporine (ceftizoxime), is presented. MATERIAL AND METHODS: 2.5 mg of ceftizoxime, 6.25 mg sodium dithionite in sodium bicarbonate buffer (pH=11.4) as a reductor agent, and 300 MBq of 99mTc were used. The final pH was adjusted to 8.4 with NaOH 0.1N. Radiochemical purity was assessed using ITLC-SG/MEK, ITLC-SG/0.9% NaCl and reverse phase HPLC. Biologic activity was assessed with the agar diffusion technique soaked with E. Coli in disks containing 10.5 microg labelled and non-labelled antibiotic. The maintenance of antibiotic activity was assessed by the diameter of the inhibition halos measured after 24 hours of incubation at 37 degrees C. RESULTS: The labelling efficiency was 94.9 +/- 2.4% (n = 20) and the complex was stable up to 6 h post-labelling. The HPLC chromatography showed five peaks: two of them at 1.7-2.0 min, which corresponds to the ceftizoxime derived product (82%-83% of the absorbance and about 90% of the radioactivity) and a third one at 4.7 min which corresponds to the intact ceftizoxime (6% of absorbance). The remaining two peaks appeared at 3.8 and 6.7 min and represented about 7%-8% of the absorbance. The antibiotic activity of the ceftizoxime-derived compound (CDC) was 83% of the unlabelled one. CONCLUSIONS: 1) The labelling method of ceftizoxime described causes a modification in its structure. 2) The 99mTc binds to the newly formed compound with high labelling efficiency and an acceptable shelf life stability. 3) The 99mTc-CDC maintains 83% of the original antibiotic activity and could be used for the detection of in vivo infection.

Ceftizoxime↗
PubMed1999

Mental disorders on the island of Formentera: prevalence in general population using the Schedules for Clinical Assessment in Neuropsychiatry (SCAN).

BACKGROUND: The aims of this two-stage epidemiological study were: to determine the prevalence of psychiatric disorders in the general population of the island of Formentera (Balearic Isles, Spain); to provide reference data for subsequent health care planning; and to test a relatively new assessment instrument, the Schedules for Clinical Assessment in Neuropsychiatry (SCAN), in a community study. METHOD: It was designed as a cross-sectional two-stage community study using the General Health Questionnaire (GHQ-28) at stage one (N = 697), and the SCAN at stage two (N = 242). RESULTS: Estimated prevalence of disorders was 21.4% according to the ICD-10 classification system. Neurotic and somatoform disorders were the most prevalent, followed by substance-related, sleep and mood disorders. Total prevalence of mental disorders showed no significant differences according to sex. As regards age, mood and anxiety disorders were most prevalent in the 30- to 50-year age group, and sleep disorders were more prevalent in the older group. CONCLUSION: Prevalences of mental disorders in Formentera are higher than those found in two-stage studies in other countries and similar to those found in most studies in Spain, despite the variety of the instruments used.

Adolescent↗
PubMed1999

Systemic mastocytosis: MRI of bone marrow involvement.

Systemic mastocytosis (SM) is an abnormal proliferation of mast cells, located in different structures: skin, bone marrow, spleen, liver and lymph nodes. Magnetic resonance imaging was prospectively performed in ten patients diagnosed by bone marrow biopsy in order to describe the different patterns of bone marrow involvement. Coronal T1-weighted spin-echo images were obtained in vertebral, pelvic, humeral and femoral bones. Depending on the extension of the cell infiltration, three patterns of bone marrow involvement were used: normal/no involvement (N), non-homogeneous (NH) and homogeneous (H). All ten patients presented bone infiltration. The patterns observed were: spine (50 % NH, 50 % H), pelvis (70 % NH), humerus 100(NH) and femur 40 % (NH). T1-weighted MR imaging is a sensitive technique for detecting marrow abnormalities in patients with systemic mastocytosis. There is no correlation between percentage of mast cells in bone marrow biopsy and extent or pattern of bone marrow involvement.

Adult↗
PubMed1999

Blood volumes and renal function in overt and subclinical primary hypothyroidism.

INTRODUCTION: Thyroid dysfunction is associated with marked alterations in cardiovascular and renal functions. In hypothyroidism, myocardial contractility, cardiac output, and oxygen consumption are decreased, whereas peripheral resistance is increased. METHODS: We assessed blood volumes and effective renal plasma blood flow (ERPF) and glomerular filtration rate (GFR) in 17 patients with overt primary hypothyroidism and in 15 of these patients when in euthyroid state after substitutive therapy. We performed the same measurements in eight patients with subclinical hypothyroidism. RESULTS: In the hypothyroid state, the plasma volume measured by dilution of 125I-albumin (APV) was higher than the calculated plasma volume (CPV) from packed red cell mass, suggesting an extravascular escape of albumin. After substitutive therapy, the CPV showed a statistical increase (P < 0.05), whereas APV remained unchanged. Both ERPF and GFR increased after thyroxine therapy (p < 0.05). In the subclinical group, blood volumes and renal function were similar to those found in the other group of patients when in the euthyroid state. CONCLUSIONS: We conclude that in primary hypothyroidism, ERPF and GFR are low, but that these values improve with substitutive therapy. CPV is a better index of the current plasma volume than APV. The difference between these two parameters suggests that the escape of albumin into the extravascular space in primary hypothyroidism is terminated by treatment. There are no clear abnormalities either in blood volumes or in renal function in subclinical hypothyroidism.

Adolescent↗
PubMed1999

[ Magnetic resonance imaging in the early diagnosis of bone marrow necrosis].

Bone marrow necrosis (BMN) is a rare entity characterised by fever and bone pain, accompanied by hypercalcemia and increased LDH. Amorphous eosinophilic material is present in the bone marrow aspirate, with isolated cells in different degrees of necrobiosis. These are frequently post-mortem findings, appearing in up to 19.8% of all autopsies, mostly after haematological malignancies with proliferative features (acute leukaemia, lymphoma). In general terms, BMN is regarded as a poor prognosis sign. Bone gammography with Tc has been included among the diagnostic procedures, in an attempt to carry out an early detection of BMN and to determine its spread. Magnetic resonance imaging (MRI) has recently been regarded useful to evaluate bone marrow involvement in this condition. A 53 year-old woman is presented here who, two and a half years after being diagnosed of mantle cell lymphoma, and having a relapse on her neck lymph nodes, presented severe bone pain showing no radiological evidence of osseous involvement. MRI showed ample spongy marrow involvement of her lower spine, sacrum and pelvic bones. Both femoral heads were preserved, hypointense images being observed in T1, whereas subcortical, hyperintense ones appeared in T2. Bone marrow aspirate showed poor cellularity, with different degrees of necrobiosis on a stippled background. The picture was interpreted as BMN secondary to non-Hodgkin's lymphoma.

Bone Marrow↗
PubMed1999

[Quantification of liver volume by SPECT].

This study aimed to optimize a method to estimate liver volume by SPECT. Several phantoms were used to simulate the liver shape with a volume between 400 and 2,500 cc. The SPECT studies were acquired using 360 degrees and 180 degrees circular orbits, 64 projections, 64 x 64 word matrix, all purpose parallel-hole collimator and were reconstructed with a HANN filter with frequency cutoff = 0.5 cycles/ pixel. The reconstructed studies were processed with a program that estimates the organ volume for different threshold cutoff levels for counting. The optimum cutoff threshold level to quantify the liver volume was 50% and 48% for 360 degrees orbits and 180 degrees orbits, respectively. A linear relationship was observed between the real and calculated volumes with r = 0.994 for the 360% orbits and r = 0.976 for the 180 degrees orbits, The average error between corrected and real volumes was 4.2% and 10.87% for both orbits, respectively. The method was applied to 14 patients with different degrees of hepatomegaly who had undergone a liver 99mTc-sulfur colloid scintigraphy. The intra and interobserver variability as well as the influence of the degree of contour adjustment of the phantom mask were studied. No significant differences were observed in the results, so that it can be considered that neither the mask trace nor the operator influence the results.

Anthropometry↗
PubMed1998

[Comparison of endoscopy, radiology and scintigraphy with Tc-99m-exametazine labeled leukocytes and In-111 labeled human polyclonal immunoglobulin G in the diagnosis of inflammatory bowel disease].

BACKGROUND: The 99mTc-exametazine labelled leukocytes (99mTc-WBC) scintigraphy is an established method for the inflammatory bowel disease (IBD) diagnosis, but the labelled procedure is a large and laborious process. The 111In-labelled human polyclonal immunoglobulin G (111In-IgG) can be an alternative in the non invasive IBD diagnosis. PATIENTS AND METHODS: Thirty-four patients routinely referred for investigation of IBD were studied. The 99mTc-WBC and 111In-IgG were simultaneously injected and images were obtained at 30 min, 3 and 24 h post-injection. The diagnostic was established by histology of endoscopy and/or surgery samples. Images were blindly evaluated by two experienced observers who only knew of the clinical suspicion of IBD. IBD was confirmed in 27 patients (17 with Crohn's disease [CD] and 10 with ulcerative colitis [UC]). RESULTS: Sensitivity, specificity and accuracy were 88.5, 100 and 90.3% respectively for endoscopy, 73.7, 75 and 73.9% for radiology, 59.3, 85.7 and 64.7% for 111In-IgG scan and 96.3, 85.7 and 94.1% for 99mTc-WBC scan. In the diagnosis of CD involvement of small bowel, the 99mTc-WBC scan identified 9/11 patients with confirmed disease, whereas the 111In-IgG scan diagnosed only four of them. In the evaluation of colonic disease, the 99mTc-WBC scan correctly diagnosed 21/22 confirmed patients, being the 111In-IgG scan positive in 13 of them. As far as disease extension concerned, the 99mTc-WBC demonstrated a statistically significance rather number of disease segments than endoscopy, radiology and 111In-IgG scan. CONCLUSIONS: The 99mTc-WBC was an effective method in the diagnosis of suspected IBD patients, both in the evaluation of small bowel disease and colonic disease, with slightly best results for colonic disease, whereas the 111In-IgG scan seems to have no utility neither in diagnosis nor in extension evaluation of IBD.

Adolescent↗
PubMed1998

[Radionuclide scan with TC-99m-tin colloid in the evaluation of orthopedic implant infections].

We have studied 26 patients (32-77 years old, 16 females) with suspicion of joint arthroplasty infection: 11 total hip replacements, 12 total knee replacements and 3 osteosinthesys. A bone scintigraphy with MDP-99mTc, a scintigraphy with HMPAO-WBC and a scintigraphy with 99mTc-stannous colloid were made in all patients. The final diagnostic was based in joint cultures and clinic and radiologic evolution of the patients. The earliest phase of the bone scintigraphy was positive in 18 patients. The later phase was positive in all them. The WBC was positive in 20 out of 26 patients. The bone marrow scintigraphy showed a congruent pattern with WBC in 18 patients (17 infected and 1 without infection). The other ones (8 patients) showed an incongruent pattern (7 with infection and 1 without it). The results show that the bone marrow scintigraphy with 99mTc-stannous colloid improves the accuracy of the diagnostic of bone prosthesis infection and should be included into the diagnosis protocol of this disease.

Adult↗
PubMed1998

[Effective renal plasma flow with I-131-hipuran: evaluation of a method with four extractions].

The aim of this work was to evaluate a method for the estimation of the effective renal plasma flow (ERPF) using sodium 131I-o-hippurate (OIH) by means the bicompartmental analysis of the radioactive concentration of 4 plasma samples, analyzing the error obtained respecting to the multi-sample method and comparing it with those obtained with other simplified methods. We calculated the ERPF from 62 patients using the multi-sample method as standard, the method based in a single sample at 44 minutes p.i., a method based in 2 samples from the first exponential, 4 methods based in 2 samples from the second exponential, one method based in 3 samples and 5 methods based in 4 samples (2 from the first exponential and 2 from the second exponential). Each simplified method was compared to the standard method and their absolute error (AE) and standard estimation error (SEE) were calculated. The method based in the 4 samples withdrawn at 4, 10, 30 and 60 minutes p.i. was the best of them with a correlation factor with the standard equal to 0.997, an EA that ranged from -63 ml/min to 49 ml/min (mean: -4 ml/min) and a SEE of 19.5 ml/min.

Body Fluid Compartments↗
PubMed1998

[Scintigraphic assessment of the severity of inflammatory bowel disease using Tc 99m exametazime-labeled leukocytes].

The aim of the work was to value the utility of semiquantitative scintigraphics indexes (GI) as predictive factor of activity grade of intestinal inflammatory process in patients with confirmed diagnosis of inflammatory bowel disease (IBD). 64 patients have been studied (39 males and 25 females), mean age was 40,2 years (range: 18-88 years) with diagnosis of IBD in acute exacerbation confirmed by endoscopy and biopsy. In all patients was obtained abdominal scintigraphy with 99mTc-exametazine labelled leukocytes. The severity of intestinal inflammatory process was quantified using clinical indexes -Truelove-Witts index (TI) for ulcerative colitis (UC) and Crohn's disease activity index (CDAI), Harvey index (HI) for Crohn disease (CD)-, endoscopic index (EI) and haematological parameters: erythrocyte sedimentation rate (ESR), hematocrit, haemoglobin, leukocyte and platelet count, fibrinogen and albumin level. In all the scans regions of interest were drawn over liver, spleen, bone, abdominal background and positive intestinal segments. Subsequently three GI were calculated: GI1, GI2 and GI3 for the scans obtained at 30 min (P) and 3 h p.i. (T). The evaluation of UC severity showed significant correlation between: 1) The GI1 P and T and TI, EI, ESR, leukocyte and platelet count; 2) The GI2 P and TI and EI; 3) The IG2 T and EI, hematocrit and platelet count; 4) The GI3 P and TI, EI, ESR and platelet count; 5) The GI3 T and TI, EI, leukocytes and platelet count. In the evaluation of CD was observed significant correlation between the GI1 P and GI3 P with the CDAI and EI, between the GI1 T and the GI3 T with the CDAI and ESR; the GI2 did not show significant correlation with any of the valorised parameters. In conclusion, the scintigraphic activity indexes based in the semiquantitative evaluation of scans obtained with 99mTc-exametazine labelled leukocytes showed usefulness in the evaluation of the IBD severity, especially in the UC. Among the studied indexes, IG1 seems the more accurate.

Adolescent↗
PubMed1997

[Comparative study of an expert system application in the prescription of medications].

BACKGROUND: The aim of this study was to evaluate the impact of a expert drug system implementation on the drug prescription habits and on drug cost in an university hospital. MATERIAL AND METHODS: During a 3 months period, the drug prescriptions to patients admitted to the Internal medicine, lung, gastroenterology and hepatology units, have been evaluated through the expert drug system (Medisource). This expert drug system functions in according to patients characteristics such as age, weight, height, sex, renal function and liver function. It recommends the correct dose, detects interactions and adverse effects and makes suggestions in pregnancy and lactation. It also offers alternative drugs with their cost. During the study period physicians were unaware of the investigation being performed. RESULTS: 836 patients (63.9 +/- 16.5 years) with an average hospital stay length of 11.6 +/- 6.7 days were studied. The most common diagnoses were: lung obstructive chronic disease, cirrhosis, gastrointestinal hemorrhage and cancer. The total amount of drug prescribed was 6,308. The expert system detected 458 overdosages and 33 underdosages, mainly in antibiotics and antiulcer drugs, and 1,722 interactions. The drug costs reduction that could be obtained following the expert system recommendations was 4.5% in antibiotic drugs and 23% in antiulcer drugs. CONCLUSION: The frequency of drug overdosage and underdosage in patients admitted in an university hospital is relatively high. The expert systems available for drug decisions could solve this problem.

Aged↗
PubMed1997

Radiation myelopathy in over-irradiated patients: MR imaging findings.

The objective of this work is to report the MRI findings in patients with radiation myelopathy due to accidental local over-irradiation syndrome. Eight patients (seven males and one female) were suffering from over-irradiation syndrome as a result of treatments from a malfunctioning linear electron accelerator. The mean accidental estimated dose was 136 Gy delivered to the "open-neck" (seven cases) and to the thoracic wall (one case), during a mean of 5.4 sessions (range 1-9 sessions). Paresthesia and weakness in the upper extremities were the earliest symptoms (87.5 %), with evolution to paralysis in all patients. No patient is alive (mean survival time 64 days). In all cases MRI was negative for neurologic lesions in the acute phase ( < 90 days from irradiation; Radiation Therapy Oncology Group scoring system). Late signs of radiation myelitis manifested as high-intensity signals on T2-weighted images in three patients, and as Gd-DTPA enhancement of T1-weighted images in one case. Autopsies performed on four patients who died in acute phase showed morphologic alterations in white matter: edema in 75 %, and necrosis and glial reaction as well as obliterative vasculitis in all cases. In cases of over-irradiation, MRI may be normal in acute phase even if the patients have severe neurologic deficit, as positive MRI findings appear only in delayed radiation myelitis.

Adult↗