Urinary plasma protein patterns in acute prostatitis

Diagnostic accuracy of urinary prostate protein glycosylation profiling in prostatitis diagnosis

INTRODUCTION

Although prostatitis is a common male urinary tract infection, clinical diagnosis of prostatitis is difficult. The developmental mechanism of prostatitis is not yet unraveled which led to the elaboration of various biomarkers. As changes in asparagine-linked-(N-)-glycosylation were observed between healthy volunteers (HV), patients with benign prostate hyperplasia and prostate cancer patients, a difference could exist in biochemical parameters and urinary N-glycosylation between HV and prostatitis patients. We therefore investigated if prostatic protein glycosylation could improve the diagnosis of prostatitis.

MATERIALS AND METHODS

Differences in serum and urine biochemical markers and in total urine N-glycosylation profile of prostatic proteins were determined between HV (N=66) and prostatitis patients (N=36). Additionally, diagnostic accuracy of significant biochemical markers and changes in N-glycosylation was assessed.

RESULTS

Urinary white blood cell (WBC) count enabled discrimination of HV from prostatitis patients (P<0.001). Urinary bacteria count allowed for discriminating prostatitis patients from HV (P<0.001). Total amount of biantennary structures (urinary 2A/MA marker) was significantly lower in prostatitis patients compared to HV (P<0.001). Combining the urinary 2A/MA marker and urinary WBC count resulted in an AUC of 0.79, 95% confidence interval (CI)=(0.70-0.89) which was significantly better than urinary WBC count (AUC=0.70, 95% CI=[0.59-0.82], P=0.042) as isolated test.

CONCLUSIONS

We have demonstrated the diagnostic value of urinary N-glycosylation profiling, which shows great potential as biomarker for prostatitis. Further research is required to unravel the developmental course of prostatic inflammation.

Characterization of the seminal plasma proteome in men with prostatitis by mass spectrometry

Background

Prostatitis is an inflammation of the prostate gland which affects approximately 10% of men. Despite its frequency, diagnosing prostatitis and monitoring patient response to treatment remains frustrating. As the prostate contributes a substantial percentage of proteins to seminal plasma, we hypothesized that a protein biomarker of prostatitis might be found by comparing the seminal plasma proteome of patients with and without prostatitis.

Results

Using mass spectrometry, we identified 1708 proteins in the pooled seminal plasma of 5 prostatitis patients. Comparing this list to a previously published list of seminal plasma proteins in the pooled seminal plasma of 5 healthy, fertile controls yielded 1464 proteins in common, 413 found only in the control group, and 254 found only in the prostatitis group. Applying a set of criteria to this dataset, we generated a high-confidence list of 59 candidate prostatitis biomarkers, 33 of which were significantly increased in prostatitis as compared to control, and 26 of which were decreased. The candidates were analyzed using Gene Ontology and Ingenuity Pathway analysis to delineate their subcellular localizations and functions.

Conclusions

Thus, in this study, we identified 59 putative biomarkers in seminal plasma that need further validation for diagnosis and monitoring of prostatitis.

Urinary tract infections in spinal cord injury: prevention and treatment guidelines

OBJECTIVES AND METHODS

The literature on prevention and therapy of urinary tract infection (UTI) in patients with spinal cord injury (SCI) was reviewed using 3 levels of evidence.

RESULTS

Antibiotic therapy is only indicated in symptomatic bacteriuria or in symptomatic exacerbations of chronic UTI. During the acute phase of a SCI, UTI's are more prevalent and bacteria are different and more resistant to antibiotics compared with the chronic phase of SCI. In SCI in general, routine screening urine cultures are not valuable as a high species turn over is seen. Intermittent catheterisation, tapping or Crédé manoeuvre coincide significantly with lower frequency of UTI compared to permanent catheter drainage. No measures are proven efficient in the long term in prevention of bacteriuria or UTI. Methenamine salts are perhaps useful in the prevention of UTI but not in patients with a permanent catheter (level III). Antibiotic prophylaxis was found useful in reducing asymptomatic bacteriuria but not in the prevention of symptomatic infections (level I). However, during prophylaxis a doubling of antibiotic resistance was found. In patients with augmented bladder antibiotic prophylaxis is useless (level II). In chronic SCI the first choice antibiotics are nitrofurantoin or trimethoprim, the second choice are fluoroquinolones (level III) whereas in acute SCI a higher resistance profile to antibiotics is frequent and therefore fluoroquinolones or cefuroxime are suggested (level III). There is no consensus in the literature but we suggest 5 days of antibiotic treatment in UTI during chronic SCI without fever, 7 days in acute SCI without fever and a minimum of 14 days in patients with UTI and fever (level III).

New screening diagnostic techniques in urinalysis

New technological evolutions have enabled new diagnostic approaches in urinalysis. Urinary flow cytometry and automated microscopic pattern recognition are two new techniques that are characterised by a much better imprecision and a higher throughput as compared to conventional microscopy of the urine sediment. Although these new techniques are well suited for the routine clinical laboratory for screening and diagnostic purposes, trained technicians are still required to verify, and if necessary, to correct the results by visual microscopy. On the other hand, automated urinary test strip analysis offers analytical, clinical, and labour cost-saving advantages. Furthermore, determination of specific urinary proteins offer interesting alternatives for diagnosis. In diabetics, the clinical significance of non-immunoreactive microalbumin needs to be established. Furthermore, the determination of specific urinary proteins alpha 1 microglobulin (as a tubular marker protein), alpha 2 macroglobulin (as a haematuria location marker) and light chains (myeloma monitoring) offer interesting diagnostic perspectives. As the information content obtained by urinalysis is complex, expert systems that make use of the various chemical and morphological parameters can offer an interesting help in the interpretation.

Prostatitissyndrom

Prostatitis syndrome is a multifactorial disease with a largely unknown etiology. Quite different therapeutic options are therefore recommended. According to the new NIH classification, pathogens can be cultured only in acute and chronic bacterial prostatitis. A long-term antimicrobial therapy, mainly with fluoroquinolones, is then recommended. Most patients suffer from chronic pelvic pain syndrome (CP/CPPS) which can be subdivided into inflammatory and non-inflammatory types. Whether the inflammatory CP/CPPS is an infectious disease remains uncertain. The effect of an antibiotic therapy therefore remains debatable. In case of proven or suspected functional infravesical obstruction, treatment with a-receptor blockers is recommended. Accompanying symptomatic therapy is also recommended. It is important, however, to keep the patient fully informed about the diagnostic and therapeutic limitations.

Alpha 1-microglobulin: clinical laboratory aspects and applications

BACKGROUND

Urinary microproteins are becoming increasingly important in clinical diagnostics. They can contribute in the non-invasive early detection of renal abnormalities and the differentiation of various nephrological and urological pathologies. Alpha 1-microglobulin (A1M) is an immunomodulatory protein with a broad spectrum of possible clinical applications and seems a promising marker for evaluation of tubular function.

METHOD

We performed a systematic review of the peer-reviewed literature (until end of November 2003) on A1M with emphasis on clinical diagnostic utility and laboratory aspects.

CONCLUSIONS

A1M is a 27-kDa glycoprotein, present in various body fluids, with unknown exact biological function. The protein acts as a mediator of bacterial adhesion to polymer surfaces and is involved in inhibiting renal lithogenesis. Because A1M is not an acute phase protein, is stable in a broad range of physiological conditions and sensitive immunoassays have been developed, its measurement can be used for clinical purposes. Unfortunately, international standardisation is still lacking. Altered plasma/serum levels are usually due to impaired liver or kidney functions but are also observed in clinical conditions such as HIV and mood disorders. Urinary A1M provides a non-invasive, inexpensive diagnostic alternative for the diagnosis and monitoring of urinary tract disorders (early detection of tubular disorders such as heavy metal intoxications, diabetic nephropathy, urinary outflow disorders and pyelonephritis).