A candidate serum biomarker for bladder pain syndrome/interstitial cystitis

Rapid Biomarker-Based Diagnosis of Fibromyalgia Syndrome and Related Rheumatologic Disorders by Portable FT-IR Spectroscopic Techniques

Fibromyalgia syndrome (FM), one of the most common illnesses that cause chronic widespread pain, continues to present significant diagnostic challenges. The objective of this study was to develop a rapid vibrational biomarker-based method for diagnosing fibromyalgia syndrome and related rheumatologic disorders (systemic lupus erythematosus (SLE), osteoarthritis (OA) and rheumatoid arthritis (RA)) through portable FT-IR techniques. Bloodspot samples were collected from patients diagnosed with FM (n = 122) and related rheumatologic disorders (n = 70), including SLE (n = 17), RA (n = 43), and OA (n = 10), and stored in conventional protein saver bloodspot cards. The blood samples were prepared by four different methods (blood aliquots, protein-precipitated extraction, and non-washed and water-washed semi-permeable membrane filtration extractions), and spectral data were collected with a portable FT-IR spectrometer. Pattern recognition analysis, OPLS-DA, was able to identify the signature profile and classify the spectra into corresponding classes (Rcv > 0.93) with excellent sensitivity and specificity. Peptide backbones and aromatic amino acids were predominant for the differentiation and might serve as candidate biomarkers for syndromes such as FM. This research evaluated the feasibility of portable FT-IR combined with chemometrics as an accurate and high-throughput tool for distinct spectral signatures of biomarkers related to the human syndrome (FM), which could allow for real-time and in-clinic diagnostics of FM.

Metabolomics in Central Sensitivity Syndromes

Central sensitization syndromes are a collection of frequently painful disorders that contribute to decreased quality of life and increased risk of opiate abuse. Although these disorders cause significant morbidity, they frequently lack reliable diagnostic tests. As such, technologies that can identify key moieties in central sensitization disorders may contribute to the identification of novel therapeutic targets and more precise treatment options. The analysis of small molecules in biological samples through metabolomics has improved greatly and may be the technology needed to identify key moieties in difficult to diagnose diseases. In this review, we discuss the current state of metabolomics as it relates to central sensitization disorders. From initial literature review until Feb 2020, PubMed, Embase, and Scopus were searched for applicable studies. We included cohort studies, case series, and interventional studies of both adults and children affected by central sensitivity syndromes. The majority of metabolomic studies addressing a CSS found significantly altered metabolites that allowed for differentiation of CSS patients from healthy controls. Therefore, the published literature overwhelmingly supports the use of metabolomics in CSS. Further research into these altered metabolites and their respective metabolic pathways may provide more reliable and effective therapeutics for these syndromes.

Recurrent episodes of feline lower urinary tract disease with different causes: possible clinical implications

CASE SERIES SUMMARY

While descriptions of cats with recurrent episodes of feline idiopathic cystitis (FIC) exist, little is published on cats with recurrent episodes of feline lower urinary tract disease (FLUTD) where the cat is diagnosed with different causes of FLUTD at separate episodes. In the present paper, six cats, originally part of larger studies of FLUTD among Norwegian cats, are described. In the project period (2003-2009), these cats had several episodes of FLUTD. At each episode, the cats had a complete physical examination, abdominal imaging, blood work, urinalysis and urine culture performed. Two of the cats initially presented with urolithiasis and subsequently with episodes of non-obstructed FIC. Four of the cats presented with non-obstructed FIC at one or more episodes, but were later diagnosed with urolithiasis or bacterial cystitis without prior catheterisation or other known predisposing factors.

RELEVANCE AND NOVEL INFORMATION

Cats with recurrent episodes of FLUTD may present with different causes at different times. The need to thoroughly work-up cats with recurrent episodes of FLUTD at each presentation is emphasised. FIC may be considered as a predisposing factor in cats developing urolithiasis or bacterial cystitis; alternatively, interrelated FLUTD disease mechanisms exists. Thus, applying multimodal environmental enrichment and modification (MEMO) to cats with signs of FLUTD independent of diagnosis should be considered.

Metabolic fingerprinting for diagnosis of fibromyalgia and other rheumatologic disorders

Diagnosis and treatment of fibromyalgia (FM) remains a challenge owing to the lack of reliable biomarkers. Our objective was to develop a rapid biomarker-based method for diagnosing FM by using vibrational spectroscopy to differentiate patients with FM from those with rheumatoid arthritis (RA), osteoarthritis (OA), or systemic lupus erythematosus (SLE) and to identify metabolites associated with these differences. Blood samples were collected from patients with a diagnosis of FM (n = 50), RA (n = 29), OA (n = 19), or SLE (n = 23). Bloodspot samples were prepared, and spectra collected with portable FT-IR and FT-Raman microspectroscopy and subjected to metabolomics analysis by ultra-HPLC (uHPLC), coupled to a photodiode array (PDA) and tandem MS/MS. Unique IR and Raman spectral signatures were identified by pattern recognition analysis and clustered all study participants into classes (FM, RA, and SLE) with no misclassifications (p < 0.05, and interclass distances > 2.5). Furthermore, the spectra correlated (r = 0.95 and 0.83 for IR and Raman, respectively) with FM pain severity measured with fibromyalgia impact questionnaire revised version (FIQR) assessments. Protein backbones and pyridine-carboxylic acids dominated this discrimination and might serve as biomarkers for syndromes such as FM. uHPLC-PDA-MS/MS provided insights into metabolites significantly differing among the disease groups, not only in molecular m/z+ and m/z- values but also in UV-visible chromatograms. We conclude that vibrational spectroscopy may provide a reliable diagnostic test for differentiating FM from other disorders and for establishing serologic biomarkers of FM-associated pain.

Serum Cytokine Profiling in Cats with Acute Idiopathic Cystitis

BACKGROUND

Feline idiopathic cystitis (FIC) is a common lower urinary tract disorder of domestic cats that resembles interstitial cystitis/painful bladder syndrome (IC/PBS) in humans. Diagnosis of FIC is based on clinical signs and exclusion of other disorders because of a lack of specific pathologic findings or other objective biomarkers. Cytokines are potential noninvasive biomarkers to define the presence, severity, and progression of disease, and response to treatment.

OBJECTIVES

The objective of this pilot study was to determine concentrations of selected cytokines in serum from healthy cats and cats with acute FIC.

ANIMALS

Serum samples from 13 healthy cats and from 12 cats with nonobstructive acute FIC were utilized.

METHODS

Multiplex analysis of 19 cytokines (CCL2, CCL5, CXCL1, CXCL12, CXCL8, Flt3L, GM-CSF, IFN-γ, IL-12 (p40), IL-13, IL-18, IL-1β, IL-2, IL-4, IL-6, PDGF-BB, SCF, sFas, and TNF-α) was performed with a commercially available feline-specific multiplex bead-based assay.

RESULTS

Mean serum concentrations of IL-12 (p40; P < 0.0001), CXCL12 (P = 0.002), IL-18 (P = 0.032), and Flt3L (P = 0.0024) were significantly increased in FIC cats compared to healthy cats. GM-CSF, IL-1b, IL-2, and PDGF-BB were undetectable or detected in an insufficient number of cats to allow meaningful comparisons.

CONCLUSIONS AND CLINICAL IMPORTANCE

We have identified increased serum concentrations of pro-inflammatory cytokines and chemokines CXCL12, IL-12, IL-18, and Flt3L in FIC-affected cats. These findings suggest potential candidates for noninvasive biomarkers for diagnosis, staging, and therapeutic outcome monitoring of affected cats and provide additional insight into the etiopathogenesis of FIC.

The Challenges of Interstitial Cystitis: Current Status and Future Prospects

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a syndrome of unpleasant bladder sensations and lower urinary tract symptoms. The three main proposed etiologies are bladder urothelial dysfunction, bladder inflammation (possible neurogenic), and neuropathic pain. Despite decades of basic and clinical research, IC/BPS remains difficult to treat. A variety of treatments are used, each aimed towards one etiology. For example, glycosaminoglycans are thought to improve the urothelial permeability barrier, anti-inflammatory agents are used to decrease general inflammation, and mast cell stabilizers and/or antagonists of mast cell products are used in the treatment of neurogenic inflammation. In the (unfortunately frequent) event that a treatment fails, possible reasons are that (1) the clinician is aiming towards the wrong etiology for that patient (i.e., the treatment is off target) or (2) the correct etiology is being targeted, but the treatment is not ameliorating it (i.e., the treatment is sub-therapeutic). This is a crucial distinction, because an off-target treatment should be abandoned, but a sub-therapeutic treatment should be escalated. Currently, our inability to make this crucial distinction is the greatest obstacle to effective treatment. An important future advance would be to identify urine or serum biomarkers specific to each etiologic target. Then, each biomarker could be used to select appropriate patients for each treatment and monitor the treatment's effect on its intended target.

Elevated level of nerve growth factor in the bladder pain syndrome/interstitial cystitis: a meta-analysis

Objectives

To elucidate the association between nerve growth factor (NGF) level and bladder pain syndrome/interstitial cystitis (BPS/IC) by conducting a meta-analysis.

Methods

We conducted a systematic literature search to identify original studies of NGF level in BPS/IC before November 2015. Eligible studies were retrieved via both computer searches and manual review of references. The summary difference estimates between controlled group and BPS/IC group were calculated based on the weighted mean difference (WMD) with its 95 % confidence interval (CI). Sensitivity and publication analyses were performed after the pooled analysis.

Results

Meta-analysis of 10 original studies involving 295 cases and 290 normal controls showed an increased level of urinary NGF in BPS/IC patients (z = 3.08, P = 0.002). The combined WMD was 36.39 (95 % CI 13.27–59.51). There was significant difference between controlled group and BPS/IC patients in the term of NGF/Cr level (WMD = 0.96, 95 % CI 0.58–1.35; z = 4.89, P < 0.01). There was no significant publication bias in the included studies (P for Begg’s test = 0.73, P for egger’s test = 0.13).

Conclusions

Our results demonstrated that there was an increased level of NGF in the BPS/IC patients.

From bladder to systemic syndrome: concept and treatment evolution of interstitial cystitis

Interstitial cystitis, presently known as bladder pain syndrome, has been recognized for over a century but is still far from being understood. Its etiology is unknown and the syndrome probably harbors different diseases. Autoimmune dysfunction, urothelial leakage, infection, central and peripheral nervous system dysfunction, genetic disease, childhood trauma/abuse, and subsequent stress response system dysregulation might be implicated. Management is slowly evolving from a solo act by the end-organ specialist to a team approach based on new typing and phenotyping of the disease. However, oral and invasive treatments are still largely aimed at the bladder and are based on currently proposed pathophysiologic mechanisms. Future research will better define the disease, permitting individualization of treatment.

Management of refractory OAB in the non-neurogenic patient

Overactive bladder (OAB) is one of the most common bothersome urological diseases. It also has a negative economic impact. Pathophysiology entails changes in neurogenic and myogenic factors, as well as urinary biomarkers such as nerve growth factor (NGF) and prostaglandins (PGs). With symptoms from OAB-Dry to OAB-Wet, the urodynamic pattern of OAB bladder is often characterized by idiopathic detrusor overactivity with lower threshold of sensation, diminished compliance and capacity. Treatment ranges from a combination of behavioral modifications (BM)/ pelvic floor muscle training (PFMT) to combinations of antimuscarinics, Botox injection, nerve stimulation and augmentation cystoplasty. Herein, a contemporary review on the different aspects of management of refractory OAB in patients without neuropathic disorders is presented.

AAFP and ISFM Guidelines for diagnosing and solving house-soiling behavior in cats

RATIONALE

These Guidelines have been developed by the American Association of Feline Practitioners (AAFP) and the International Society of Feline Medicine (ISFM) as a resource for veterinary practitioners who want to better understand and manage the important clinical condition of house-soiling in their feline patients. The Guidelines offer straightforward, practical solutions that, in most cases, will help veterinarians and cat owners prevent, manage or entirely remediate feline house-soiling behavior.

EVIDENCE BASE

The Guidelines include scientifically documented information when it is available. However, because research is often lacking, some recommendations reflect the accumulated clinical experience of the authors.

A bloodspot-based diagnostic test for fibromyalgia syndrome and related disorders

The aim of this study was to investigate the ability of a rapid biomarker-based method for diagnosis of fibromyalgia syndrome (FM) using mid-infrared microspectroscopy (IRMS) to differentiate patients with FM from those with osteoarthritis (OA) and rheumatoid arthritis (RA), and to identify molecular species associated with the spectral patterns. Under IRB approval, blood samples were collected from patients diagnosed with FM (n = 14), RA (n = 15), or OA (n = 12). Samples were prepared, placed onto a highly reflective slide, and spectra were collected using IRMS. Spectra were analyzed using multivariate statistical modeling to differentiate groups. Aliquots of samples also were subjected to metabolomic analysis. IRMS separated subjects into classes based on spectral information with no misclassifications among FM and RA or OA patients. Interclass distances of 15.4 (FM vs. RA), 14.7 (FM vs. OA) and 2.5 (RA vs. OA) among subjects, demonstrating the ability of IRMS to achieve reliable resolution of unique spectral patterns specific to FM. Metabolomic analysis revealed that RA and OA groups were metabolically similar, whereas biochemical differences were identified in the FM that were quite distinctive from those found in the other two groups. Both IRMS and metabolomic analysis identified changes in tryptophan catabolism pathway that differentiated patients with FM from those with RA or OA.

Methods and incentives for the early diagnosis of bladder pain syndrome/interstitial cystitis

INTRODUCTION

The concept of interstitial cystitis (IC) has changed dramatically during the last decades, eventually representing a symptom complex with varying contents. To include all patients with bladder pain, the umbrella term 'bladder pain syndrome' (BPS) has been suggested, incorporating the classic presentation of IC as a separate phenotype. This change of concepts has not been uncontroversial. Bladder pain syndrome often has a profound effect on the patients' quality of life. Generally, recognition of this problem complex is hampered by insufficient familiarity in the medical community. The correct diagnosis is often delayed by several years and may be preceded by multiple medical consultations and treatment attempts. There is no doubt that an early and correct diagnosis is of great significance for the patient.

AREAS COVERED

In this article, a critical review of methods and means to approach the diagnosis is presented including some notes of current controversies.

EXPERT OPINION

The key to an early diagnosis is symptom recognition. We are dealing with a heterogeneous concept including various phenotypes. The successful treatment requires understanding and expedient use of objective means, such as cystoscopy, biopsy and input from the multidisciplinary team. In the literature, limited evidence exists for the management of BPS/IC, due to heterogeneity in methodology and description of the syndrome(s). A more consequent use of available methods is desirable. For the immediate future, better understanding of the aetiology, pathogenesis and presentation of various BPS/IC phenotypes is indispensable.