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L Velásquez Jones

Publications and source records attributed to L Velásquez Jones.

At least 19 recordsLinked to original sources
PubMed1988

Bacterial-induced diarrhoea.

In diverse parts of the world, many bacterial strains have been recognised as the causative agents of diarrhoea. Great achievements have been made in perceiving the varied mechanisms which explain their intestinal pathogenicity. These achievements include the elucidation of the 5 mechanisms of disease production by Escherichia coli, the mechanisms of action of Shigella, Salmonella, Campylobacter and Yersinia, new information about antimicrobial-associated colitis caused by Clostridium difficile and the recognition of microbes such as Aeromonas hydrophila and Pleisomonas shigelloides. Information is available on the use and indications of antimicrobial treatment in children with diarrhoea of bacterial aetiology which is proven or suspected by clinical symptomatology or simple laboratory procedures. Finally, the usefulness of oral rehydrating solutions has been appreciated in the prevention as well as in the correction of diarrhoeal dehydration.

Bacterial Infections↗
PubMedDate not supplied

[Chronic interstitial nephritis caused by analgesics].

Interstitial nephritis secondary to analgesic ingestion is apparently an uncommon subject in pediatric literature. Two cases are reported in this article: case 1 is a girl followed for the last fifteen years when she had lipoid nephrosis which was treated initially with corticosteroids; she responded satisfactorily, but presented frequent relapses. After 8 years, she was given cyclophosphamide plus prednisone and lately, she responded and has remained well. Further on, her urinalysis showed specific gravity of 1,033 and no proteinuria. Five years ago, because of protracted headache due to psychological disturbance, she started to ingest a variety of analgesics in progressively increasing doses. For the last 2 years, abdominal pains, paleness, polydipsia and polyuria have been observed; at present, her blood pressure, serum chemistry, and urine sediment are normal, but there is a marked failure in the renal concentration capacity, as well as marked sodium urinary losses. A percutaneous renal biopsy showed tubulo-interstitial fibrosis and edema with normal glomeruli. Case 2 is a girl with rheumatoid arthritis which appeared 3 years ago; for over one year, the patient was given 15 mg/day prednisone plus 1.5 g. acetylsalycilic acid. She was admitted to the hospital because her osteoarticular problem did not improve. Her blood pressure, blood chemistries and urinary sediment were also normal. LE tests were negative. Renal concentrating capacity was reduced and the renal biopsy showed tubular atrophy; there was intestinal edema and mononuclear infiltration. Chronic interstitial nephritis, secondary to analgesics is supported in both cases; polyuria and a marked defect of renal concentrating capacity are the earliest and most characteristic features. Normal urinary sediment is a common finding leading to erroneous assessment of a lack of renal involvement. Pathological lesions are located in the interstice of the renal medulla and sometimes in the papilla. Early arrest of analgesic ingestion may stop and even reverse the renal lesion and the renal insufficiency.

Adrenal Cortex Hormones↗
PubMedDate not supplied

[Comparison between the 3- and the 24-hour urine collection for creatinine clearance].

Endogenous creatinine clearance was studied in thirty children with various renal diseases and variable degrees of functional deterioration. Two different procedures or urine collection were used on each child: 1) twenty-four-hour urine collection with one blood sample and immediately afterwards 2) three one-hour consecutive periods of urine collection, with one previous blood sample (the one used for the 24-hour procedure). Both procedures were carried out during hydration of the patient and creatinine was determined with the autoanalyzer in urine and blood samples. The results obtained with both procedures did not show significant difference. The three-hour periods procedure may be recommended for hospitalized patients, specially infants or young children, and also when the parents are not reliable enough for hydrating the patients and for performing a complete collection of urine in a 24 hour period.

Adolescent↗
PubMedDate not supplied

[Fever of unknown origin. Presentation of 180 pediatric cases].

Fever of unknown origin (FUO) is a frequent disorder in pediatric age. FUO is defined as the presence of fever over 38.4 centigrades in a patient for more than three weeks in which the etiology remains undetermined. From 30.736 consecutive admittances into our hospital, 180 patients with FUO were detected, and studied in a systematized way and according to a predetermined protocol. FUO was commonly found in children under six years of age. Our patients presented fever from three weeks to six and a half years of evolution; however, in the vast majority of the cases (n = 115) fever had a three weeks course. Several symptoms and physical manifestations other than fever were observed in our patients but they were widely variable and nonspecific. Infectious diseases were the commonest etiological factor encountered; among them, thyroid fever, and urinary tract infections were the most frequent infectious disorder found; in four children fever was associated to ampicillin administration; in 19 patients, fever was no demonstrated. A large number of laboratory investigations were done in the diagnosis of neoplastic diseases. We think that the study of a patient with FUO requires of a systematized approach.

Adolescent↗
PubMedDate not supplied

[Hypocalcemic vitamin D-dependent renal rickets].

Two siblings, female 10 years old, and male 15 years old, with the diagnosis of vitamin D-dependent rickets were studied. Another sibling, also with the same diagnosis, died of bronchopnemonia at about 7 months of age. Both patients developed rachitic manifestations since the first year of life, which persisted despite the administration of massive doses of vitamin D intermitently. Severe hypocalcemia, moderate hypophosphatemia and elevated serum alkaline phosphatase were the most characteristic biochemical findings. Both patients showed diminished renal tubular reabsorption of amino acids and phosphates. These alterations were reversible during I.V. calcium gluconate administration. The clinical biochemical and X-ray manifestations disappeared completely after one year of treatment with dihydrotaquisterol. Vitamin D-dependent rickets is an autosomal recessive disease, characterized by a hydroxylation defect of 25 hydroxycholecalciferol at the carbon 1 level, due to abscence of 25 hydroxy-D1-hydroxylase. Thus 1-25 Dihydroxycholecalciferol, the active form of vitamin D3 is not formed, resulting in depression of intestinal calcium absorption and reabsorption from the bones.

25-Hydroxyvitamin D3 1-alpha-Hydroxylase↗
PubMedDate not supplied

[Medical examination for first admission students at the University of Mexico. Characteristics and evaluation of a computerized system].

Four hundred and thirty, first admission university students underwent medical examination during the school period 1979-1980. After the application of the electronic processed medical inquest, the final clinical diagnosis was reached. In 87% of the cases, a final diagnosis was worked out, whereas the remaining 13% was considered clinically healthy. Likewise, the proportion of final clinical diagnoses that were found to be correlated with the probability diagnoses issued by the inquest system wer above 60% in the following systems: digestive, E.N.T., respiratory, genitourinary and dermatological. On the other hand, on studying the final clinical diagnoses determined by the physician and that were not worked out by the computerized medical inquest system, variable proportions were observed in the different organs and systems that were investigated. Thus, it is concluded that medical inquest used at present for the study of health problems involving the first admission student population at the University of Mexico, is a useful procedure that requires a continuous evaluation to improve its effectiveness and trustworthiness, but that has allowed to cover adequately the demand for medical care among the above mentioned population.

Adolescent↗
PubMedDate not supplied

[Polyuria].

Polyuria is an important clinical sign that may pass unnoticed to the relatives and to the physician. In this paper, the definition of polyuria and the pathophysiological bases that condition its presence are reviewed. Likewise, the causes of polyuria in pediatric ages are discussed; this allows the clinician to approach the diagnosis in a systematized and organized manner. Finally, the outstanding clinical and laboratory findings of the entities that usually go with polyuria are reviewed; some of them are: neurogenic diabetes insipidus, primary polydipsia, osmotic diuresis, and nephrogenic diabetes insipidus.

Diabetes Insipidus↗
PubMedDate not supplied

[Proteinuria].

The finding of proteinuria in the pediatric age is a frequent phenomenon. Once detected, the immediate goal is to investigate other evidences of renal disease or its participation in systemic diseases. If proteinuria is an isolated finding, its transitoriness, persistence or relation with posture must be determined. Transitory proteinuria is a mild finding with good outlook; however, in patients with orthostatic or persistent asymptomatic proteinuria, the prognosis is uncertain; however, the measures taken must be conservative without restriction of physical activity and only in case of association to other signs, or finding of any change in renal function tests, the possibility of renal biopsy should be evaluated. The presence of proteinuria above 1 g/l. in a patient with acute nephritic syndrome, may be a sign of poor prognosis if it persists over one month and is indicative of renal biopsy. If this same degree of proteinuria is found in a nephrotic syndrome without hematuria or arterial hypertension, the necessity to practice renal biopsy is not indicated, except in the case it does not disappear following adequate treatment with corticosteroids.

Humans↗