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Biomedical subjects

S Vaidyanathan

Publications and source records attributed to S Vaidyanathan.

At least 91 records · Page 5Linked to original sources
PubMed1997

Urine leakage from the umbilicus in a child with achondroplasia and tetraplegia (due to cervical stenosis): a safety vent for the obstructed neuropathic bladder.

Urine leakage from the umbilicus was observed while expressing urine by the Crede manoeuvre in a three-year-old tetraplegic girl with a chronically distended urinary bladder. Intravenous urography (IVU) revealed bilateral hydroureteronephrosis with markedly distended urinary bladder. Regular three hourly intermittent catheterization was advised, and the parents and carers of this child agreed to perform catheterization. There was cessation of urine leak within 48 hours of urethral drainage. Cystography performed two weeks later showed no vesicoureteric reflux; vesicoumbilical fistula was no longer demonstrable. Follow-up IVU, performed after eight and half months of regular intermittent catheterization, showed regression of hydroureteronephrosis. We believe that urine leakage from the umbilicus served two important protective functions in this child, viz. (1) it prevented possible vesical or renal rupture; (2) the striking clinical symptom of urine leak from the umbilicus focussed the attention of the carers to the underlying serious condition of the urinary tract. Further, this case demonstrates that regression of marked hydroureteronephrosis can be achieved by intermittent catheterization performed at regular intervals by devoted parents/carers, in selected cases of spinal cord injury with neuropathic bladder, and vesical outlet obstruction, thus obviating the need for any form of temporary or permanent urinary diversion.

Achondroplasia↗
PubMed1996

Epidermal growth factor receptor in the vesical urothelium of paraplegic and tetraplegic patients: an immunohistochemical study.

Spinal cord injury (SCI) patients are at high risk of developing cystitis, and vesical neoplasia. As abnormal growth regulation of urothelium may be a predisposing factor for cystitis and vesical neoplasia, we studied alterations if any, in the expression and localization of epidermal growth factor receptor (EGRF) in the vesical urothelium by an immuno-histochemical technique, using monoclonal mouse anti-human epidermal growth factor receptor antibody (DAKO-EGFRI) in cold-cup biopsies taken from the trigone of the urinary bladder in 18 adult SCI patients who had a neuropathic bladder. Abnormal localisation of EGFR-p, i.e. cytoplasmic, was noted in 13 patients. A linear localization of EGFR-p along the cell membrane of the urothelium, considered as an essential requirement for effective function, was observed in only three cases. Combined cytoplasmic and cell membrane location of EGFR-p was seen in two patients. The three patients with cell membrane location of EGFR-p showed a strong expression of EGFR-p (2+, 2-3+, and 4+, respectively); the intensity of EGFR-p expression in cases of cytoplasmic immunostaining varied considerably. Histopathology revealed denuding cystitis in one; follicular cystitis in four; active inflammatory infiltrate in three; lymphocytic infiltrate in three; squamous metaplasia in six; and intestinal metaplasia in three biopsy specimens. The three specimens showing cell membrane location of EGFR-p were from patients who did not have an indwelling urethral catheter (a paraplegic man practising intermittent self-catheterisation, a tetraplegic patient on penile condom drainage, and a tetraplegic woman with reflex voiding), and histopathology revealed very little inflammatory infiltrate. In contrast, the biopsies from all the nine patients, who were on indwelling urethral catheter drainage and in whom the bladder biopsy revealed varying degree of cystitis, showed only cytoplasmic location of EGFR-p. Similarly, the biopsies from patients with bladder stone (n = 6) showed only cytoplasmic localisation of EGFR-p. In conclusion, abnormalities in vesical urothelial expression in EGFR in SCI patients may play a role in the pathogenesis of cystitis, vesical urothelial metaplasia, dysplasia and neoplasia.

Adult↗
PubMed1996

Endoscopic management of urethral trauma in male spinal cord injury patients.

Spinal cord injury (SCI) patients with a neuropathic bladder are more prone to develop catheter-induced urethral trauma than occurs in the general population because many of the SCI patients are on indwelling urethral catheter drainage, or intermittent urethral catheterisation is performed either by them or by their carers. The presenting symptoms of improperly positioned Foley catheter in SCI patients may be at times, peculiar to the SCI patients and these include profuse sweating, bypassing of the catheter, increased spasms, or rarely, full fledged features of autonomic dysreflexia. With the availability of the flexible cystoscope, cystourethroscopy has been performed safely on SCI patients who had sustained catheter-induced urethral trauma, on the bedside, with an immediate, and accurate diagnosis of the extent of urethral trauma, and the presence of urethral false passage(s). Further, flexible cystoscopy has helped to treat the patients with urethral trauma by introducing a flexible tip guide wire under vision into the urinary bladder via the normal urethral channel and subsequently, passing a 12 Fr. Foley catheter over the guide wire, thus avoiding the false passage(s) in the urethra. With this technique, it was possible to avert the need for suprapubic urinary diversion in those SCI patients who had sustained acute urethral trauma. Such endoscopic management of acute urethral trauma in SCI patients is described with illustrative case reports of eight patients seen during a 15 month period.

Cystoscopy↗
PubMed1996

Intravenous salbutamol treatment for penile erection arising during cystoscopy of cervical spinal cord injury patients.

Two patients with long-standing tetraplegia after spinal cord injury developed reflex penile erection in the operation theatre. One had not received any anaesthesia, and penile erection occurred after introduction of the cystoscope into the urethra, and also autonomic dysreflexia. Intravenous salbutamol, in a dose of 10 micrograms, produced immediate and persistent penile detumescence and salbutamol-induced fall in blood pressure was of therapeutic value. In the second patient, penile erection occurred during general anaesthesia prior to cystoscopy. Immediate and persistent penile detumescence was achieved with intravenous salbutamol 20 micrograms. There was transient fall of blood pressure which responded to intravenous infusion of 0.9% sodium chloride. Salbutamol-induced fall in blood pressure is of therapeutic value in those spinal cord injury patients who develop, in addition to penile erection, autonomic dysreflexia precipitated by urethral instrumentation, or bladder distension with the irrigating fluid. Intravenous salbutamol is preferable to intra-cavernosal phenylephrine, noradrenaline, metaraminol, and epinephrine, or intravenous ephedrine which are contraindicated in patients with hypertension.

Adrenergic beta-Antagonists↗
PubMed1996

Unusual complications of intermittent self-catheterisation in spinal cord injury patients.

Three unusual complications of intermittent self-catheterisation in spinal cord injury patients observed over a period of 30 months are described. (1) Two patients performing intermittent catheterisation with a PVC catheter requiring the use of lignocaine gel to numb the urethra, developed allergic reaction in the form of swelling and erythematous lesions around the external urethral meatus. This rare complication was overcome by switching over to the use of a Lofric catheter instead of a PVC catheter for intermittent catheterisation. (2) Urethral bleeding was observed on three occasions in male paraplegic patients performing intermittent self-catheterisation who had allowed the bladder to become over-distended. Bladder emptying therefore, took nearly 10 min, by which time the Lofric catheter became too sticky in the urethra and required undue force for withdrawal, resulting in trauma to the adherent urethral mucosa and urethral bleeding. By adopting the policy of catheterisation at regular intervals and not allowing the bladder to become distended beyond 450 ml of urine, this complication was never seen again either in these three patients or in any other patient using Lofric catheter for intermittent urethral catheterisation. (3) Failure to drain urine after urethral catheterisation resulting in a panic reaction was observed in a 45 year old woman practising intermittent catheterisation. This unique complication happened because there were no eye holes on the Nelaton catheter.

Adult↗
PubMed1996

Nerve fibres in urothelium and submucosa of neuropathic urinary bladder: an immunohistochemical study with S-100 and neurofilament.

Intravesical administration of drugs has been used commonly in spinal cord injury patients to suppress detrusor hyperreflexia (eg oxybutynin, verapamil, terodiline) or, to initiate a micturition reflex (eg 15S 15-methyl prostaglandin F2 alpha, protaglandin E2); however, the response has been variable and sometimes, unpredictable. This prompted us to study the presence of nerve fibres in the vesical urothelium and submucosa in mucosal biopsies taken from the dome and trigone (obtained prior to performing a therapeutic procedure eg, vesical lithotripsy, or a diagnostic cystoscopy) in 47 consecutive, unselected paraplegic/tetraplegic patients with a neuropathic urinary bladder. Nerve fibres were demonstrated by routine immunohistochemical technique using commercially available monoclonal and polyvalent antibodies against S-100 (DAKO A/S, Glostrup, Denmark) and Neurofilament (MILAB, Malmo, Sweden). Biopsy specimens were graded for the presence of nerve fibres on a 0-3 scale for urothelium, and superficial/deep submucosa separately in a blind and randomised manner. Virtually no fibre presence was found in one paraplegic patient and no superficial or single fibres were noted in a tetraplegic patient. Absence of C-fibre hyperplasia (Grade 0) was found in nine cases (paraplegic: 4; tetraplegic: 5); Grade 1 hyperplasia was observed in 17 cases (paraplegic: 4; tetraplegic: 13); Grade 2 hyperplasia was seen in 11 cases (paraplegic: 7; tetraplegic 4); and Grade 3 hyperplasia was noticed in eight cases (paraplegic 3: tetraplegic: 5). The magnitude of C-fibre hyperplasia was not significantly different between paraplegic and tetraplegic patients (chi(2) = 4.64; P = 0.3262). The relationship, if any, between the degree of C-fibre hyperplasia and duration of paralysis was studied by categorising patients as < 5 years, and > 5 years of paralysis. No evidence of single fibre or fibre bundle hyperplasia (Grade 0) was seen in five and six cases, grade 1 hyperplasia in six and 11 cases, grade 2 hyperplasia in two and nine cases, and grade 3 hyperplasia in three and five cases respectively in these two categories of patients. (chi(2) = 1.92; P = 0.58). The possible relationship between C-fibre hyperplasia in the vesical mucosa/submucosa and (i) the vesical response to intravesical drug administration; (ii) the vesical urothelial proliferation arrest; (iii) the electrical stimulation of urinary bladder by implanted electrodes (sacral anterior root stimulator); and (iv) long-term indwelling urethral Foley catheter drainage, are discussed with illustrative case reports. In conclusion, mucosal biopsy and study of nerve fibres in urothelium and submucosa of neuropathic bladder has helped to generate hypotheses on the association between C-fibre hyperplasia and response to intravesical pharmacotherapy and the predictive value of such a study in identifying those patients who are likely to respond to intravesical pharmacotherapy.

Adult↗
PubMed1996

T-cell predominant balanitis in a traumatic tetraplegic patient: a case report.

T-cell predominant balanitis is described in a 38 year old uncircumcised tetraplegic man whose presenting feature was non-progressive red lesions over the inner prepuce and the glans penis without signs of infection, phimosis, or meatal stenosis. There was no regional lymphadenopathy. He was not exposed to any of the high risk factors for human immunodeficiency virus infection. As the lesion did not respond to topical antibacterial, antifungal, and corticosteroid medications applied in that order, circumcision was performed. Following circumcision, the remaining lesion over the glans penis regressed completely over a period of 1 month. Histopathology of the excised prepuce revealed that both areas of normal nonkeratinizing squamous epithelium as well as areas with hyperplasia. No atypia was noted and Bowenoid changes were not seen. Immunohistochemical studies on the inflammatory infiltrate in the excised prepucial lesion using tissue proliferation markers (PCNA and MIB-1) revealed active proliferation of the band-like infiltrate shown by immunophenotyping (anti-human T cell, CD45RO, clone UCHL1 and L26, pan-B marker) to consist predominantly of T-cells, further supporting the hypothesis of a local immune-mediated inflammatory process as the final pathogenic mechanism of the penile lesion.

Adult↗
PubMed1996

Effect of epidural buprenorphine and clonidine on vesical functions in women.

Buprenorphine (4 micrograms/kg body weight) and clonidine (3 micrograms/kg body weight) were administered epidurally to investigate their effect on vesical function in 20 American Society of Anaesthesiologists Classification I (ASA I) adult females. Cystometry was performed before and 30 minutes following epidural administration of drugs. Epidural administration of buprenorphine increased the maximum cystometric capacity from 352 +/- 98.5 - 462.8 +/- 167.3 ml (p < 0.05). There was no significant change in detrusor pressure at maximum cystometric capacity, in vesical compliance, maximum flow rate, and in the mean flow rate. Epidural administration of clonidine did not produce any significant change in the above urodynamic parameters. None of the patients in both groups developed retention of urine.

Adrenergic alpha-Agonists↗
PubMed1995

Effect of lipids on glycoprotein sulphotransferase activity in rat submandibular salivary glands.

Although glycoprotein sulphation has been implicated in the processing of salivary mucin, little is known about the regulation of the enzyme responsible for this event. Using desulphated glycoprotein as sulphate acceptor, the glycoprotein sulphotransferase (GPST) from Golgi membranes of submandibular salivary gland was used to study the effect of various lipids on its activity. The GPST activity in the Golgi membrane was 0.7 pmol/mg protein per min and the activity was extractable by Triton S-100. The Km of the solubilized GPST for glycoprotein and 3'-phosphoadenosine 5'-phosphosulphate (PAPS) were 11 and 0.2 microM, respectively. Among the various lipids tested, phosphatidylinositol and sphingosine stimulated the GPST activity, while other lipids such as sphingomyelin, phosphatidylcholine and phosphatidylserine did not produce a significant effect. At 12 mol% (when expressed as mol% of sphingosine to total phospholipids plus Triton X-100) of sphingosine concentration, the enzyme activity was increased nearly 1.7-fold. The stimulatory effect of sphingosine was accompanied by a significant decrease in Km for glycoprotein from 11 to 2 microM but the increase in Vmax was small. In contrast, the sphingosine effect did not change the Km for PAPS but increased the Vmax nearly two fold. Of the two sphingosine analogues tested, threosphinganine and erythrosphinganine had a lesser stimulatory effect than sphingosine. Stearylamine was partially active, whereas the amino acids (glutamate, aspartate, glutamine, asparagine and serine) were not. These observations and our earlier finding of tyrosylprotein sulphotransferase inhibition by sphingosine demonstrate diverse sphingosine effects on the post-translational sulphation involved in the processing of salivary proteins and suggest an important role for sphingosine in the regulation of salivary protein sulphation.

Animals↗
PubMed1995

The University of Massachusetts technique of radical retropubic prostatectomy.

A modified technique of radical retropubic prostatectomy is described which takes advantage of combining the antegrade dissection of prostate described by Skinner and the early control of prostatic vasculature as publicized by Walsh. Integration of both techniques of radical retropublic prostatectomy has resulted in improved exposure and minimal blood loss. The average blood loss with this technique was 500 ml in contrast to the average blood loss of 1100 ml while performing over 300 radical retropubic prostatectomies by the standard technique. The average operating times have been 150 minutes. Because of improved exposure and reduced blood loss, it is easy to teach this technique of radical prostatectomy to the surgeon in training (resident or the registrar) without any compromise to the primary goal of surgery which is to remove all tumour. No intra-operative complications were encountered during the performance of this modified technique of radical retropubic prostatectomy.

Blood Loss, Surgical↗
PubMed1995

Vesical urothelium proliferation in spinal cord injured persons: an immunohistochemical study of PCNA and MIB.1 labelling.

Urinary tract infection occurs more commonly, is more virulent and proves more difficult to eradicate in spinal cord injury persons than in the neurologically intact. In order to find out the peculiarities of the neuropathic bladder which make it vulnerable to recurrent cystitis, we studied the proliferation status of the urothelium in spinal cord injured persons. Eleven consecutive, unselected male spinal cord injury patients (aged 18-73 years) were included in the study. Those with, or undergoing treatment for acute urinary tract infection were excluded. All patients underwent cystoscopy and cold cup bladder biopsy from the trigone and bladder dome. Immunocytochemical analysis was performed using defined, commercially available antibodies for PCNA (PCNA 10, DAKO) and MIB-1 (raised against recombinant DNA defined segment of Ki-67 antigen DAKO) streptavidin/biotin and alkaline phosphatase immunocytochemistry (for MIB-1 with microwave-enhanced antigen retrieval) were used to demonstrate the presence of cell cycling-associated nuclear proteins. Foci of lymphocytic aggregations present in the sections served as in-section controls for antigen preservation. Ten patients showed labelling of 20-70% of cells for PCNA in basal cell layers of dome lining. Higher urothelial layers showed a variable, but generally reduced degree of labelling. Of these 10 patients, three showed complete absence of MIB-1 activity in the basal and other layers of dome urothelium and two demonstrated only a very occasional positive nucleus. MIB-1 labelling was < 5% in four others and it was between 5% and 10% in one.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗