Hyaluronan and myeloperoxidase in human peritoneal fluid during genital inflammation

Analysis of myeloperoxidase activity in wound fluids as a marker of infection

Background

Neutrophilic polymorphonuclear leukocytes play a crucial role in the host defence against bacterial and fungal infections. They participate in the inflammatory response through the liberation of peptides and enzymes like myeloperoxidase (MPO). Therefore, MPO has a potential as a marker enzyme for the diagnosis of wound infection.

Methods

Substrate specificities and reaction pathways of MPO were investigated for new MPO substrates: crystal violet, leuco crystal violet, fast blue RR (4-benzoylamino-2,5-dimethoxybenzenediazonium chloride hemi(zinc chloride) salt) and various systematically substituted model substrates based on 2,7-dihydroxy-1-(4-hydroxyphenylazo)naphtalene-3,6-disulphonic acid. In addition, fast blue RR was covalently bound to siloxanes allowing immobilization of the substrate, while cellobiosedehydrogenase was integrated for generation of hydrogen peroxide required by MPO.

Results

Elevated concentrations of MPO were found in infected wounds compared with non-infected wounds (92.2 ± 45.0 versus 1.9 ± 1.8 U/mL). Various soluble and immobilized substrates were oxidized by MPO in wound samples and the influence of substrate structure and reaction pathways were elucidated for selected compounds.

Conclusions

Incubation of different MPO substrates with infected wound fluid samples resulted in a clear colour change in the case of elevated MPO concentrations, thus allowing early diagnosis of wound infection.

The role of hyaluronic acid in wound healing: assessment of clinical evidence

Hyaluronic acid (hyaluronan), a naturally occurring polymer within the skin, has been extensively studied since its discovery in 1934. It has been used in a wide range of medical fields as diverse as orthopedics and cosmetic surgery, but it is in tissue engineering that it has been primarily advanced for treatment. The breakdown products of this large macromolecule have a range of properties that lend it specifically to this setting and also to the field of wound healing. It is non-antigenic and may be manufactured in a number of forms, ranging from gels to sheets of solid material through to lightly woven meshes. Epidermal engraftment is superior to most of the available biotechnologies and, as such, the material shows great promise in both animal and clinical studies of tissue engineering. Ongoing work centers around the ability of the molecule to enhance angiogenesis and the conversion of chronic wounds into acute wounds.

Influence of laser irradiation on endogenous hyaluronan in rabbit iris and aqueous humor

PURPOSE

To monitor changes of endogenous hyaluronan in the iris tissue and aqueous humor after an isolated trauma to the iris by argon laser irradiation of the anterior surface of the iris.

METHODS

Iris and aqueous hyaluronan concentrations in rabbit were measured with a radiometric assay at different time points after laser irradiation.

RESULTS

Total hyaluronan content in iris tissue increased 3-fold to a peak concentration of 71-72 microg/g at 1 and 2 days after laser treatment. Aqueous hyaluronan increased to a maximum of about 1.6 microg/ml at 2 h and 12 h after laser irradiation of the iris.

CONCLUSIONS

The iris tissue responds with increased hyluronan synthesis to an isolated iris argon laser irradiation and it seems to be the most important source of aqueous hyaluronan.

Pleural fluid myeloperoxidase as a marker of infectious pleural effusions

Background: The aim of this study was to establish the diagnostic accuracy of neutrophil markers (elastase, lysozyme, myeloperoxidase) found in pleural fluid in differentiating between infectious and non-infectious pleural effusions (PE). Methods: We studied 184 patients over 18 years of age with PE, classified as either infectious (34 complicated parapneumonic, 32 non-complicated parapneumonic, 45 tuberculous) or non-infectious (31 neoplasms and 42 undiagnosed exudates). Polymorphonuclear elastase (PMN-E) was determined using an immunoactivation method and lysozyme using a turbidimetric method. Myeloperoxidase (MPO) was measured by double antibody competitive radioimmunoassay. Receiver operating characteristic (ROC) curves were used to evaluate diagnostic accuracy. Results: Pleural fluid MPO was the biochemical marker that best differentiated between infectious and non-infectious PE. The ROC area under the curve (AUC) for myeloperoxidase was 0.86. MPO values over 550 &mgr;g/l diagnosed infectious PE with a specificity of 90.4% and a sensitivity of 77.4%. After excluding purulent parapneumonic PE, the sensitivity of a pleural MPO value >/=550 &mgr;g/l was 72.6%. Conclusions: Pleural fluid MPO was the marker that best differentiated between infectious and non-infectious PE.

Fibrinolysis in the peritoneal fluid during adhesions, endometriosis and ongoing pelvic inflammatory disease

The concentrations of the specific activators (u-PA and t-PA) and the specific inhibitors (PAI-1 and PAI-2) of the fibrinolytic system were analyzed in the peritoneal fluid in women suffering from intra-abdominal adhesions, endometriosis or pelvic inflammatory diseases (PID). Peritoneal fluids were collected from ten women in whom a laparotomy was performed and an additional 108 in whom a laparoscopy was carried out. In comparison with the normal control patients all activators and inhibitors were significantly increased in cases of PID and when a second-look laparoscopy was performed one week after laparotomy with adhesiolysis. At laparoscopies, when adhesions were verified, u-PA in the peritoneal fluid was significantly increased and in cases of endometriosis PAI-2 was significantly reduced. The start of a laparotomy in order to remove adhesions, initiates a process, resulting in a significant increase of PAI-2 antigen in the pelvic fluid. The results imply that the fibrinolytic system is comprehensively activated in the peritoneal cavity during ongoing inflammatory reaction, and after adhesiolysis. The increase in plasminogen activators in the peritoneal fluid in established cases of pelvic adhesions or endometriosis may indicate that the fibrinolytic system is continuously active to inhibit the further formation of adhesions.

Retrograde migration of starch in the genital tract of rabbits

This study in a rabbit model simulates contamination with glove powder in association with a routine gynaecological examination. Large individual variations of powder contamination were found and there were no overall statistically significant differences between the control and experimental animals. The findings are supported by the observation that some but not all women develop adhesions after gynaecological surgery. Analyzes of variances indicate differences in the migration of starch particles in the genital tract with the highest amount of particles found three days after starch contamination of the vagina. Since no adhesions were observed, there would probably need to be an ongoing post surgical or post infectious inflammation in the tissue, when the starch particles are added. Starch powder from latex gloves can cause adhesions and increase the risk of latex allergy in healthcare workers. Retrograde migration in the genital tract cannot be excluded, powdered examination products should be eliminated from the gynecologicla examination room.

Serum hyaluronan as a disease marker

Hyaluronan is a connective tissue polysaccharide which has also been found in blood serum in concentrations < 100 micrograms/L (average 30-40 micrograms/L in middle-aged persons). The serum level is regulated by the influx of the polysaccharide from the tissues via lymph and its receptor-mediated clearance by liver endothelial cells. Markedly high serum levels are noted in certain liver diseases, especially in patients with cirrhosis, when the clearance is impaired. In these cases serum hyaluronan can be used to follow the development of the disease. Serum hyaluronan is also a sensitive marker for impending rejection of liver transplants. Patients with rheumatoid arthritis constitute another major group with increased serum hyaluronan, but in this case the level varies markedly during the day corresponding to physical activity. There are good indications that in these subjects the excess hyaluronan comes from the joints. Under stringent sampling conditions of serum it should be possible to extract interesting information on the inflammatory joint process. Increased hyaluronan levels are also seen in other inflammatory diseases and it is of special interest that high hyaluronan levels in patients with septic conditions is a sign of poor prognosis. Certain tumours, notably Wilms' tumour and mesothelioma, produce factors which activate synthesis of hyaluronan and increase its serum level. Rare hereditary diseases with disturbances of hyaluronan metabolism and elevated blood levels have also been discovered, e.g. Werner's syndrome and cutaneous hyaluronanosis. Information accumulated during the last decade regarding the metabolism of hyaluronan has made this polysaccharide an interesting clinical marker for a number of pathological conditions.

Role of eosinophilic granulocytes in women with infertility and pelvic adhesions

Increased numbers of eosinophilic granulocytes and eosinophil degranulation have been observed in various inflammatory conditions. Biopsies from the fallopian tubes of 28 patients were examined for the content of eosinophilic granulocytes. Peritoneal fluids (PF) from 89 patients were analyzed for the concentrations of eosinophilic granulocytes and the granule protein eosinophil cationic protein (ECP). The ECP levels in the PF were substantially elevated during genital inflammation (P < 0.001). Furthermore, one week after laparotomy for adhesiolysis there were both increased PF-ECP levels (P < 0.01) and raised concentrations of eosinophilic granulocytes (P < 0.001) when compared to the reference group. Staining of the biopsies with monoclonal antibodies revealed an increased total number as well as a number of activated eosinophilic granulocytes in specimens from adhesions and sactosalpinx compared to specimens from normal fimbriae. The findings indicate that eosinophilic granulocytes may have a possible role in the fibrotic process of pelvic adhesion disease.