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F Di Silverio

Publications and source records attributed to F Di Silverio.

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

Transforming growth factor beta 1 and androgen receptors in prostate neoplasia.

OBJECTIVE: To investigate the interplay between transforming growth factor (TGF) beta 1, androgen receptors and stromal-epithelial interactions in benign prostatic hyperplasia (BPH), prostate intraepithelial neoplasia (PIN) and prostate carcinoma areas of prostate neoplasia. STUDY DESIGN: In this immunohistochemical study we investigated staining patterns and then determined the correlation between TGF-beta 1 expression and androgen receptor status in the epithelium and stroma of 60 paraffin-embedded tissues from radical prostatectomies. RESULTS: Staining patterns differed in the epithelium and stroma of tumor and peritumor prostatic tissue. TGF-beta 1 immunostaining (H-scores) in the epithelium and stroma increased significantly from BPH to PIN and from BPH to prostate carcinoma in the epithelium (P < .05), whereas androgen receptor (AR) immunoreactivity significantly (P < .05) increased from BPH to PIN to prostatic carcinoma in epithelium and stroma. TGF-beta 1 did not correlate with histologic grade of differentiation, whereas AR proteins were more strongly expressed in Gleason score 5 and 6 than score 7 tumors (P < .05). Nonlinear regression showed a significant correlation (P < .01) between TGF-beta 1 and AR expression only in the stromal compartment of PIN. CONCLUSION: These findings argue in favor of an interaction between TGF-beta 1 and AR in the early stages of prostate carcinogenesis and suggest that TGF-beta 1 plays a central role in stromal-epithelial interactions during the early stages of malignant transformation.

Aged↗
PubMed2000

[Role of nitric oxide in the urogenital system: physiology and pathology].

A review has been made on the role of nitric oxide in the physiology and pathophysiology of penis, bladder, prostate and the nervous structures involved in the urinary control. NO is an essential mediator in penile erection and his action can be modulated by sildenafil. Nitric oxide could be involved in bladder detrusor relaxation and in the development of interstitial cystitis. Little is known about the role of nitric oxide in the physiology and pathophysiology of the prostate: this molecule is released by the epithelial and stromal cells of the prostate, and by the prostatic nerves. Actually some studies hypothesize a role played by nitric oxide in benign prostatic hyperplasia development.

Humans↗
PubMed2000

Intermittent androgen deprivation (IAD) in patients with localized prostate cancer and a biochemical progression after radical prostatectomy.

BACKGROUND: To analyze the modifications in serum PSA levels during IAD in patients with an initial PSA progression after radical retropubic prostatectomy (RRP). METHODS: Between February 1994 and May 1996, 34 consecutive patients with an initial PSA progression (> 0.4 ng/ml) after RRP were selected. All men had localized adenocarcinoma of the prostate, stage pT2 pN0 M0. Patients were offered IAD when PSA progressed over 0.4 ng/ml. The initial treatment period with complete androgen deprivation (CAD) lasted 24 weeks in all cases. After, an acceptable nadir PSA level was considered to be a value < or = 0.4 ng/ml. CAD was then with held until serum PSA increased to a value over 0.4 ng/ml. RESULTS: Follow-up ranges from 144 to 228 weeks. The median time for the first 5 treatment cycles was 32, 24, 28, 32 and 32 weeks respectively, with a median time "off" therapy that increased from 8 weeks (first cycle) to 22 weeks (fifth cycle). The median nadir PSA value during "on" treatment period was 0.20 ng/ml in all 5 cycles. So far, in none of the patients did a serum PSA fail to decrease during "on" treatment period. CONCLUSIONS: We suggest that IAD may be an effective therapy in patients with an initial PSA progression after RRP. However, large prospective studies are needed to confirm these results and to better understand the meaning of PSA variations.

Adenocarcinoma↗
PubMed1999

Nitric oxide synthases in normal and benign hyperplastic human prostate: immunohistochemistry and molecular biology.

The expression of nitric oxide synthase (NOS) isoforms has been investigated in normal (three subjects) and benign hyperplastic prostate (ten patients) by immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR). The inducible NOS (iNOS or NOS-2) is not detected in normal prostate, while it is expressed in the prostate of all benign prostatic hyperplasia (BPH) patients, even in the absence of prostatitis or systemic signs of an inflammatory condition. This suggests that sex hormones may be involved in iNOS induction and that there may be a role for NO in the pathogenesis of BPH. Constitutive NOSs (nNOS and eNOS) are expressed in both normal and hyperplastic prostate and are co-expressed in epithelial cells. eNOS, however, is present mainly in the basal layer cells; nNOS seems abundantly expressed in the more superficial cells of the affected prostate. This indicates that the switching between the two constitutive isoforms may be part of the usual process of cell differentiation from the basal to the secretory layer of the epithelium.

Aged↗
PubMed1999

Hormone-refractory prostate cancer? Anti-androgen withdrawal and intermittent hormone therapy.

OBJECTIVE: To separate hormone-dependent from hormonally relapsed prostate cancers, a D3 category has been proposed. The term has become synonymous with a hormone-refractory state with the implication that any further hormonal treatment would not be beneficial. In this review we examine some data on androgen receptor expression, anti-androgen withdrawal syndrome and intermittent androgen deprivation (IAD) in patients with advanced prostate cancer. MATERIALS: The literature on the mechanism of the withdrawal phenomenon in patients with prostate cancer submitted to hormone therapy was reviewed. Experimental and clinical data are reported. RESULTS: The progression of prostate cancer in patients treated with combined androgen blockade (CAB) is associated with the activation of previously androgen-repressed genes, some of which may code for autocrine and paracrine growth factors that substitute for androgens in maintaining the viability of the tumorigenic stem cells. If androgens are replaced before progression begins, the surviving stem cells should give rise to an androgen-dependent tumor, which would be amenable to retreatment by CAB. This theory provides the rationale for intermittent androgen deprivation. We suggest that IAD could be more effective in patients with initial prostate-specific antigen (PSA) progression after radical prostatectomy. CONCLUSIONS: Response to withdrawal therapies or second-line treatments is an example of a "hormonal" therapy that may benefit a proportion of patients with hormone-refractory disease, suggesting that the tumor is still androgen-dependent. Whether IAD enhances progression-free survival or overall survival must be verified in randomized clinical trials. Until further studies have been completed, the therapeutic concept of IAD should be treated as experimental.

Androgen Antagonists↗
PubMed1999

Can the intraprostatic concentration of epidermal growth factor influence the variance of serum prostate specific antigen levels in patients with benign prostatic hyperplasia?

PURPOSE: Except for prostate volume, little is known about the factors influencing serum prostate specific antigen (PSA) levels. Considering that dihydrotestosterone and epidermal growth factor are regulators of the proliferation and differentiation in the epithelial component of human prostate tissue and that PSA is produced only by the epithelial cells of the gland, studies were performed on patients with a histological diagnosis of benign prostatic hyperplasia (BPH) to establish whether a significant association exists between the intraprostatic concentration of dihydrotestosterone or epidermal growth factor and serum PSA levels. MATERIALS AND METHODS: A total of 20 patients with BPH who had not been previously treated were part of a larger study on the correlation among PSA, prostate volume and age, and were evaluated according to the algorithm in the guidelines of the international consultation on BPH. All men underwent open suprapubic prostatectomy to enucleate the entire adenoma and in each case sections were made in the periurethral, subcapsular and intermediate zones of the BPH tissue. Dihydrotestosterone and epidermal growth factor concentrations were evaluated by radioimmunoassay in the periurethral zone and in total BPH tissue. RESULTS: In these 20 patients with BPH serum PSA levels were significantly associated with epidermal growth factor but not with dihydrotestosterone concentrations in total BPH tissue (r = 0.7762, p = 0.00002836 and r = 0.3923, p = 0.0956307, respectively). A stronger association was found between PSA levels and the periurethral concentration of epidermal growth factor and dihydrotestosterone (r = 0.8117, p = 0.000005 and r = 0.5656, p = 0.0098326, respectively). On the contrary, epidermal growth factor and dihydrotestosterone were not significantly associated with prostate volume (p = 0.957415 and p = 0.531439, respectively). CONCLUSIONS: To our knowledge this study is the first report in the literature to demonstrate an association between serum PSA, and dihydrotestosterone and epidermal growth factor levels, particularly in the periurethral zone of human BPH tissue. These data suggest the importance of epidermal growth factor and dihydrotestosterone in influencing serum PSA levels.

Aged↗
PubMed1999

[Limitations on the interpretation of prostate-specific antigen serum levels].

Recent data suggest that PSA expression can be directly influenced by some factors, independently from the variation in prostate cell growth. Some growth factors such as fibroblast growth factor, transforming growth factor beta and epidermal growth factor, seem to be directly involved in the regulation of mRNA-PSA expression, whereas androgens could have an indirect activity. On the basis of these experimental data, this review tries to analyze some limits of PSA and some recent data on the role of PSA-isoforms, in particular in the follow-up of prostate cancer patients submitted to radical prostatectomy or hormone-therapy. Moreover, relevant informations can be obtained analyzing the variance of PSA in patients submitted to intermittent androgen deprivation.

Androgens↗
PubMed1999

Is hyperdiploidy of immature ejaculated germ cells predictive of testis malignancy? A comparative study in healthy normozoospermic, infertile, and testis tumor suffering subjects.

The possibility of diagnosing neoplastic testis pathologies by studying immature germ cells released from the seminiferous epithelium and present in the semen has been reported. It has been suggested that carcinoma in situ (CIS) of the testis and testis tumor may be identified by studying specific surface antigenic determinants or ploidy of chromosome 1 of malignant germ cells recovered from the semen. A noninvasive diagnostic approach of this type would be of great interest if we consider that CIS is supposed to precede the development of testicular germ cell tumors and that the frequency of that preneoplastic condition is increased in specific andrologic pathologies. To evaluate the reliability of this diagnostic approach, we have quantified the presence of immature hyperdiploid germ cells in the seminal fluid of normal healthy subjects, of infertile oligozoospermic patients affected by maldescended testis or left vancocele, and of patients suffering from CIS or testis tumor. Cell ploidy was evaluated on seminal cell fractions highly enriched in immature germ cells, by means of in situ hybridization with a DNA-probe specific for chromosome 1. Our observations indicate that chromosome 1 hyperdiploidy is not necessarily a predictive parameter of testis tumoral pathologies. The percentage of hyperdiploid immature seminal germ cells is in fact increased in nontumoral pathologies associated with infertility, such as cryptorchidism and left varicocele.

Adult↗
PubMed1998

Effects of long-term treatment with Serenoa repens (Permixon) on the concentrations and regional distribution of androgens and epidermal growth factor in benign prostatic hyperplasia.

BACKGROUND: The n-hexane lipido-sterol extract of Serenoa repens (LSESr, Permixon, Pierre Fabre Medicament, Castres, France), a phytotherapeutic agent used in the treatment of benign prostatic hyperplasia (BPH), has a multisite mechanism of action including inhibition of types 1 and 2 5alpha-reductase and competitive binding to androgen receptors in prostatic cells. Here, the response of testosterone (T), dihydrotestosterone (DHT), and epidermal growth factor (EGF) in BPH tissue of patients treated with LSESr (320 mg/day for 3 months) is analyzed. METHODS: BPH samples were sectioned in periurethral, subcapsular, and intermediate regions: in each region T, DHT, and EGF were determined by radioimmunoassay after purification on celite columns or Sep-pak C18 cartridges. RESULTS: In the untreated group, T, DHT, and EGF presented the highest concentrations in the periurethral region (615 +/- 62 (SE) pg/g tissue, 7,317 +/- 551 pg/g tissue, and 20.9 +/- 3.3 ng/g tissue, respectively) with respect to the peripheral subcapsular region (425 +/- 45 pg/g tissue, 4,215 +/- 561 pg/g tissue, and 10.8 +/- 1.4 ng/g tissue, respectively). In the LSESr-treated group, a statistically significant reduction was observed, mainly in the periurethral region of DHT (2,363 +/- 553 pg/g tissue, P < 0.001) and EGF (6.98 +/- 2.48 ng/g tissue, P < 0.01), with increased T values (1,023 +/- 101 pg/g tissue, P < 0.001). CONCLUSIONS: The decrease of DHT and the rise of T in BPH tissue of patients treated with Permixon confirms the capacity of this drug to inhibit in vivo 5alpha-reductase in human pathological prostate. A marked decrease of EGF, associated with DHT reduction, was also observed. These biochemical effects, similar to those obtained with finasteride, are particularly evident in the periurethral region, whose enlargement is responsible for urinary obstruction, with respect to the subcapsular region. A possible speculation is that the preferential reduction of DHT and EGF content in the periurethral region is involved in the clinical improvement of the obstructive symptoms in BPH during LSESr therapy.

Aged↗
PubMed1998

Relationship among age, prostate-specific antigen, and prostate volume in men with lower urinary tract symptoms (LUTS) and in different groups of men with and without benign and malignant prostate diseases.

BACKGROUND: In order to enhance prostate-specific antigen (PSA) as a predictor of prostate cancer, it is necessary to understand the characteristics of this tumor marker in a population of men without evidence of prostate cancer but who are at risk for developing the condition. METHODS: In an age-stratified population of 328 men with lower urinary tract symptoms (LUTS), we analyzed the distribution of PSA levels as a function of age and prostate volume, and we analyzed the percentage of age-related variance in PSA that can be explained by the age-related variance in prostate volume. RESULTS: Classifying the 328 cases with LUTS according to four age groups, a correlation was found between PSA and prostate volume, becoming stronger from the younger (correlation coefficient, -0.1265) to the older group (correlation coefficient, 0.6044). Serum PSA variance per milliliter of prostate volume also increased from the younger (not significant, P > 0.1) to the older age decades (7.3% in men age 70 years or over). Moreover, the results of the regression analysis suggest that 10% of the variance in PSA with age can be accounted for by prostate volume in men under age 50 years, reaching 37% in men age 70 years or more. CONCLUSIONS: These data confirm that the serum PSA concentration increases with advancing age in the absence of clinically evident prostatic malignancy. In younger patients with LUTS, serum PSA variance with age seems to be less dependent upon the age-related variance in prostate volume.

Adult↗
PubMed1998

Relationship among symptom score, prostate volume, and urinary flow rates in 543 patients with and without benign prostatic hyperplasia.

BACKGROUND: Studies on the relationship among symptom score, urinary flow rate, and prostate volume in men with lower urinary tract symptoms (LUTS) continue to be of great interest. METHODS: A total of 2,418 men, aged 30-86 years, agreed to participate in an interview and to complete a questionnaire regarding voiding patterns. All subjects answering positively to one or more of the questions were submitted to a diagnostic assessment, based on the algorithm outlined by the guidelines of the International Consultation on Benign Prostatic Hyperplasia (BPH). Five hundred forty-three out of the 2,418 participants (22.45%) were evaluated. At the end of the diagnostic evaluation, 400 men with LUTS but without concomitant conditions (except BPH) known to interfere with normal voiding were selected. Descriptive statistics were used to characterize age, symptom score (International Prostate Symptom Score), prostate volume, and urinary flow rate distribution in these patients. Correlations among the aforementioned parameters were evaluated by means of a multivariate, multiple linear regression and logistic regression model. RESULTS: As reported in other studies, only weak or modest correlations were found. Moreover, the 400 cases were classified according to four age decades. The decrease in peak and mean flow rate per decade of age was similar (0.5 and 0.4 ml/sec); the increase in prostate volume and in total symptom score per decade was 3.3 cc and 0.6, respectively. In patients less than 50 years old, most of the correlations were stronger than those observed in the entire population of 400 men (age and prostate volume, c.c. 0.2864; age and peak flow rate, c.c. -0.2689; age and mean flow rate, c.c. -0.3034). However, symptom score continued to be weakly correlated with age and prostate volume (c.c. 0.0498 and 0.1966, respectively). In the last part of the study, men were assigned to different treatment strategies. Patients who were assigned to surgical treatment had higher prostate volume and IPSS and lower urinary flow rate than those assigned to nonsurgical treatment. CONCLUSIONS: We believe that the reason for the weak statistical association frequently reported in the literature is mainly the urology clinic-based population from which the patient samples were drawn. Data emerging from this analysis support the hypothesis that age is one of the principal factors influencing the relationship among symptom score, urinary flow rate, and prostate volume.

Adult↗
PubMed1998

[Twelve years of ureterorenoscopy: evolution of the technique].

In the last ten years the diagnostic and therapeutical approach to ureteral neoplasms and stones changed their feature, due to improvement of the ureteroscopy. The passage through flexible to rigid and finally semirigid ureteroscopes permitted reduction of invasiveness with higher results. The positive changes to the energy sources, in regard to cost-benefit, it was versus ballistic energy. Ureteroscopy should now be considered as a simple and safe technique, with minimal morbidity and invasiveness and also short operative times.

Cost-Benefit Analysis↗
PubMed1998

[The role of prostate specific antigen and its derivatives (age-specific PSA, PSA density, velocity, free/total PSA) in the diagnosis of prostate cancer].

PSA is the most useful tumor marker for the diagnosis and treatment of prostate cancer. Its clinical use, however, still lacks the necessary sensitivity and specificity to be considered as ideal. In fact PSA is not specific for adenocarcinoma of the prostate: an elevated serum level of the marker does not necessarily mean malignant growth and normal levels too often hide an occult and potentially lethal cancer. With the discovery of different molecular PSA forms in the serum, an improved discrimination between benign prostate hyperplasia (BPH) and prostate cancer appears possible. This may be particularly useful in cases with equivocal PSA values and unpalpable prostate neoplasm to reduce the number of unnecessary prostate biopsies and increase the number of biopsies in cases without palpable or ultrasonic visible anomalies. The clinical use of PSA age-referenced levels is discussed. Their use is invaluable in screening programs where the routine adoption of age-specific values can help to pick-up younger patients with potentially curable prostate cancer and older patients with BPH where additional tests would be unnecessary. The role of PSA velocity (PASAV) s also discussed. An elevation rate of PSA of 0.75 ng/ml over 18 months on 3 serial samples appears to be the best cut-off to distinguish BPH from prostate cancer. However, the use of PSAV seems to be less useful in patients with elevated PSA levels and negative biopsy results. Free to total PSA ratio is probably the best parameter to reduce the number of unnecessary biopsies in men with a serum total PSA of 4 to 10 ng/ml. The advantages and limitations for different levels of cut-off are shown. A flow chart illustrating the role of various PSA "derivatives" in screening and subsequent evaluation of men over 50 years of age is also presented.

Age Factors↗
PubMed1998

New aspects on prostate cancer: hereditary form, developmental estrogenization and differentiation therapy.

Three new different aspects of prostate cancer have been considered in this review: the existence of an hereditary form, the role of estrogens as predisposing factors and the efficacy of differentiation therapies. Prostate cancer shows a stronger familial aggregation than colon and breast carcinoma. Hereditary prostate cancer is distinguished by early age at onset and autosomal dominant inheritance within families. However, only 2% of all prostate cancer in United States white men occur in those 55 years old or younger. Thus, the impact of hereditary prostate cancer in the population is the greatest at younger ages but this accounts for only a small proportion of the total disease burden. Using the developmentally estrogenized mouse model, an alternative role for estrogens as a predisposing factor for prostate diseases was proposed: estrogen exposure during development may initiate cellular changes in the prostate which would require estrogens and/or androgens later in life for promotion to neoplasia. A combination therapy employing both differentiation therapy and hormone therapy may be effective in the treatment of advanced prostate cancers. Recent advances in the field of differentiation therapy have resulted in the development of novel retinoic acid metabolism blocking agents. Unlike previous differentiating agents such as the retinoids, these agents increase the endogenous levels of retinoic acid by inhibiting its breakdown in cancer cells.

Animals↗
PubMed1998

[Urethral implantation of collagen in the treatment of urinary incontinence. Comparison of transurethral and periurethral approach].

BACKGROUND: In mini-invasive surgery for the treatment of urinary incontinence injectable substances such as politef, autologous fat or bovine collagen, which can increase urethral resistance or support the sphincteric one are particularly used. It's a simple procedure in which patients may undergo local anesthesia, in short time and in "day hospital" regimen. Collagen, used as an injectable bulking agent, is the gold standard for this surgical technique because of complete biocompatibility, no evidences of adverse immunogenic effects, foreign-body reaction, migration of injected material, and because of higher fluidity which allows the use of thin needles compared to Politef (polytetrafluoroethylene) where an injection device is requested. Bovine collagen is partially reabsorbed within 24-36 months and a reinjection is often necessary. Although autologous fat is cheaper than bovine collagen, its injection shows more difficulties due to the need of higher needle diameter and time to store and prepare the material to inject. METHODS: The results obtained by two different approaches: transurethral injection of collagen and periurethral injection of collagen have been studied. A total of 48 patients underwent collagen injection for treatment of urinary incontinence: 24 treated by transurethral approach and 24 by periurethral approach. Follow-up at 6, 12, 24 months after treatment includes: objective exam, PAD test, functional evaluation, complete urodynamic evaluation (uroflow, cystomanometry, LPP, pressure/flow study, UPP). RESULTS: No clinical differences between peri/trans-urethral approach were found although collagen injection via transurethral technique need fewer material, reducing cost of treatment: an efficacy of treatment in 80% of patients and restoration of a complete urinary continence in 50% of patients was obtained. Although no clinical differences were demonstrated between the two different sites of injection, transurethral approach can be used similarly in both sexes even if without a modified resector as "injection device" it's more difficult to inject collagen in the right position, at the level of bladder neck submucosa. Perineal approach, exclusive of female sex, realizes the procedure without bleeding of urethral mucosa and no waste of collagen, though a longer period of training by surgeon is requested. After four years of experience the authors agreed that with an adequate injection device (modified resector), transurethral approach should be preferred, thus depending on the possibility to inject collagen in a correct position, just under bladder neck mucosa, which is possible to manage with this technique, in order to reduce reabsorption process of collagen and to obtain a longer efficacy of treatment reducing the number of reinjection and of course the cost of treatment. Collagen injection should be considered within an integrated therapeutical picture together with topic and systemic pharmacotherapy, physiotherapy, not excluding surgery techniques such as implantation of an artificial sphincter device in man or a sling procedure in woman. CONCLUSIONS: The urethral collagen injection for the treatment of urinary incontinence is a safe, durable and valid technique to improve urinary continence through a non obstructive effect increasing urethral resistance. Performed under local anesthesia this procedure allows the treatment of patients who may not be candidates suitable for general anesthesia and conventional surgery.

Adult↗
PubMed1998

Transforming growth factor-beta expression in human testicular neoplasms.

OBJECTIVE: To investigate the localization of transforming growth factors (TGF-beta 1, -beta 2 and -beta 3) and their receptors (TGF-beta RI and RII). STUDY DESIGN: The study included 26 paraffin-embedded tissues from human testicular neoplasms: 15 seminomas, 2 embryonal carcinomas, 1 immature teratoma, 4 immature teratomas with embryonal carcinoma, 1 immature teratoma with seminoma, 1 seminoma with embryonal carcinoma and 2 gonadal stromal tumors (Leydig cell tumors). RESULTS: TGF-beta 1 immunoreactivity was cytoplasmic and was expressed in 22 (84.6%), TGF-beta 2 in 20 (77%), TGF-beta 3 in 11 (42.3%), TGF-beta-RI in 21 (80.8%) and TGF-beta-RII in 18 (69.2%) of the 26 neoplasms. The percentage of positive immunostained cells and the intensity of staining were significantly higher in tumor than in peritumor nonneoplastic testis. In the peritumor nonneoplastic testis, Leydig, Sertoli and germ cells coexpressed both the three TGF-beta isoforms and TGF-beta-RI and RII. The myoepithelial cells of the seminiferous tubules showed immunoreactivity for TGF-beta RI and RII but not for TGF-beta s. In tumor testis areas the pattern of TGF-beta and TGF-beta receptor expression and distribution varied according to the histologic type of testicular tumor. Seminomas showed a diffuse pattern of TGF-beta immunoreactivity, whereas immature teratomas had focal and patchy distribution. In teratomas, differentiated structures contained more TGF-beta s than undifferentiated structures.

Activin Receptors, Type I↗
PubMed1998

Simultaneous detection of HPV and other sexually transmitted agents in chronic urethritis.

BACKGROUND: Many pathogens may be responsible of Non Gonococcal Urethritis (NGU) with the possible occurrence of symptomatic and asymptomatic mixed viral and bacterial infections. In particular, genital papillomaviruses (HPVs) have been searched since they are linked to both benign and malignant lesions of the penis and urethra and the presence of a potential male carried state has received limited scrutiny while the screening of sexually active females has received substantial attention. METHODS: In male patients affected by chronic NGU, the presence of DNA of Chlamydia trachomatis, herpes simplex virus (HSV) type 1 and 2 and human papillomaviruses by PCR and the occurrence of Gram positive and Gram negative micro-organisms, of Mycoplasma hominis and Ureaplasma urealyticum, by conventional cultural methods have been investigated. RESULTS: Results obtained indicated a high percentage of mixed infections, up to 36%. Genital HPV DNA was detected in 31% of specimens positive for two or more agents, and HSV DNA was detected in 10% of studied population. CONCLUSIONS: The concomitant presence of different infectious agents could determine latent, sub-clinical or chronic infections with periodic reactivation. In particular results suggest that HPV and HSV may stimulate cytokine production which can up regulate the expression of other infectious agents and may be responsible for latent chlamydial infections characterised by the persistence of this micro-organism in an altered form, viable but in a culture negative state. Therefore an increased awareness of mixed infections is relevant to define the management and treatment of chronic urethritis.

Adult↗