Introduction: We have investigated the accuracy of a serological marker to distinguish between septic and aseptic loosening of Total Hip Replacements (THR). We present the preliminary results of our on-going prospective study.

Methods: After obtaining Ethical Committee approval, 46 patients were collected in 3 groups; “control” primary THR, revision THR for aseptic loosening, and revision THR for infection. Serum IgG responses to an exocellular bacterial antigen (Lipid S) were determined by enzyme-linked immunosorbent assay (ELISA).

Results: Our results show that the test can accurately differentiate between the patients with infected joint replacements and the control group. The test, to date, has a specificity of 93% and a sensitivity of 100%.

Discussion and Conclusion: This simple and cheap test can reliably assist in the accurate evaluation of a painful hip arthroplasty, and planning for revision surgery. It will also be useful in the management of patients in whom the microbiology results are either negative or based on a single isolate of an organism, which may be either a contaminant or a possible pathogen. This, in turn, would have implications on financial costs and the optimum use of available resources.

Introduction and Aims: We have investigated the accuracy of a serological marker to distinguish between septic and aseptic loosening of Total Hip Replacements (THR). We present the preliminary results of our ongoing prospective study.

Method: After obtaining Ethical Committee approval, 46 patients were collected in three groups: ‘control’ primary THR, revision THR for aseptic loosening and revision THR for infection. Serum IgG responses to an exocellular bacterial antigen (LipidS) were determined by enzyme-linked immunosorbent assay (ELISA).

Results: Our results show that the test can accurately differentiate between the patients with infected joint replacements and the control group. The test, to date, has a specificity of 93% and a sensitivity of 100%.

Conclusions: This simple and cheap test can reliably assist in the accurate evaluation of a painful hip arthroplasty, and planning for revision surgery. It will also be useful in the management of patients in whom the microbiology results are either negative or based on a single isolate of an organism, which may be either a contaminant or a possible pathogen. This, in turn, would have implications on financial costs and the optimum use of available resources.

Introduction and Aims: To confirm whether bacteria were present in disc material harvested at the time of discectomy; and to determine whether the presence of bacteria correlated with elevation of Anti Lipid S antibody levels; and to compare these results with antibody levels and disc specimens from patients undergoing surgery for indications other than radiculitis.

We have previously demonstrated significantly elevated IgG titres (ELISA) to a glycolipid antigen found in the cell wall of most gram-positive bacteria in patients with discogenic sciatica. This raised the possibility that the inflammation associated with disc protrusion might be initiated or accelerated by bacteria.

Method: A prospective study was performed using disc material harvested with stringent aseptic precautions from 207 microdiscectomy and 27 trauma, tumor or scoliosis patients (controls). Serology was obtained for all patients.

Results: In the Microdiscectomy group 76/207 (37%) had positive cultures after seven days incubation, of which 26 (34%) had positive serology. Forty-nine patients had Propionibacteria, 11 Coagulase-negative-Staphylococci (CNS), eight Propionibacteria and CNS, four other organisms and four mixed growth.

One hundred and thirty one (63%) patients had negative cultures of whom 15% had positive serology. There was a significant difference between patients with positive serology and culture, compared with those with negative serology and culture (Fischer exact test P< 0.01). In some patients, organisms were visible on microscopy prior to culture. Two of the patients undergoing surgery for other indications had positive cultures (P.acnes) of whom one had positive serology. Of those with negative cultures, six had positive serology.

There was a significant difference between positive cultures in those with sciatica and controls (P< .001).

Conclusion: A significant proportion of patients with discogenic radiculitis have positive cultures with low-virulence Gram-positive organisms (predominantly Propionibacteria ) and in proportion, a corresponding appropriate antibody response.

Introduction: We have investigated the accuracy of a serological marker to distinguish between septic and aseptic loosening of Total Hip Replacements (THR). We present the preliminary results of our on-going prospective study.

Methods: After obtaining Ethical Committee approval, 46 patients were collected in 3 groups; “control” primary THR, revision THR for aseptic loosening, and revision THR for infection. Serum IgG responses to an exocellular bacterial antigen (Lipid S) were determined by enzyme-linked immunosorbent assay (ELISA).

Results: Our results show that the test can accurately differentiate between the patients with infected joint replacements and the control group. The test, to date, has a specificity of 93% and a sensitivity of 100%.

Clinical Relevance: This simple and cheap test can reliably assist in the accurate evaluation of a painful hip arthroplasty, and planning for revision surgery. It will also be useful in the management of patients in whom the microbiology results are either negative or based on a single isolate of an organism, which may be either a contaminant or a possible pathogen. This, inturn, would have implications on financial costs and the optimum use of available resources.

Introduction: We have previously demonstrated significantly elevated IgG titres (ELISA) to a glycolipid antigen found in the cell wall of most gram positive bacteria in patients with discogenic radiculitis (sciatica).

This raised the possibility that the inflammation associated with disc protrusion might be initiated or accelerated by the presence of bacteria.

Aim of the study: To confirm whether bacteria were present in the disc material harvested at the time of discectomy. To determine whether the presence of bacteria correlated with elevation of Anti Lipid S antibody levels. To compare these results with Antibody levels and disc specimens from patients undergoing surgery for indications other than radiculitis.

Methods: This was a prospective study. Recognising the frequency of contamination in clean wound culture stringent aseptic precautions were taken. Disc material was harvested from 108 microdiscectomy patients with sciatica.

Disc material was also obtained from 11 patients undergoing discectomy for other indications (trauma, tumour scoliosis). Serology was obtained for all these patients.

Results: In the microdiscectomy group 50/112 (45%) had positive cultures after seven days incubation, of which 15 (30%) had positive serology. Thirty-one patients had Propionibacteria, nine Coagulase negative Staphylococci (CNS), six Propionibacteria and CNS, one Corynebacterium and three mixed growth.

Sixty-two (55%) patients had negative cultures and all except one had negative serology. There was a significant difference between patients with positive serology and culture compared with those with negative serology and culture (Fischer exact test P< 0.01). In some patients organisms were visible on microscopy prior to culture.

Thirteen of those with postive cultures and 25 of those with negative cultures had had one or more epidural injections prior to surgery. Epidural injection was not found to be significantly associated with postive culture.

None of the patients undergoing surgery for other indications had positive serology or positive cultures.

Conclusion: A significant proportion of patients with discogenic radiculitis have positive cultures with low virulence Gram positive organisms (predominantly Propionibacteria) and in a proportion a corresponding appropriate antibody response.

Introduction: We have previously demonstrated significantly elevated IgG titres (ELISA) to a glycolipid antigen found in the cell wall of most gram positive bacteria in patients with discogenic radiculitis (sciatica).

This raised the possibility that the inflammation associated with disc protrusion might be initiated or accelerated by the presence of bacteria.

Aim of the Study: To confirm whether bacteria were present in disc material harvested at the time of discectomy. To determine whether the presence of bacteria correlated with elevation of Anti Lipid S antibody levels. To compare these results with Antibody levels and disc specimens from patients undergoing surgery for indications other than radiculitis.

Methods: This was a prospective study. Recognising the frequency of contamination in clean wound culture, stringent aseptic precautions were taken. Disc material was harvested from 62 microdiscectomy patients with sciatica. Disc material was also obtained from three patients undergoing decompression but without radiculitis and from three patients undergoing anterior correction of scoliosis. Serology was obtained for all these patients.

Results: In the Microdiscectomy group, 27/62 (43%) had positive cultures after seven days incubation, of which nine (33%) had positive serology. 22 patients had Propionibacteria, three Coagulase negative Staphylococci, one Corynebacterium and one mixed growth. Thirty five (56.4%) patients had negative cultures and all except one had negative serology. There was a significant difference between patients with positive serology and culture compared with those with negative serology and culture (Fischer exact test P< 0.001). In some patients organisms were visible on microscopy prior to culture.

Ten of those with positive cultures and fourteen of those with negative cultures had had one or more epidural injections prior to surgery. Epidural injection was not found to be significantly associated with positive culture.

None of the patients undergoing surgery for other indications had positive serology or positive cultures.

Conclusion: A significant proportion of patients with discogenic radiculitis have positive cultures with low virulence Gram positive organisms (predominantly Propionibacteria) and in a proportion, a corresponding appropriate antibody response.

Coagulase-negative staphylococci produce an exocellular glycolipid antigen which has potential as a serological marker of infection in bone. The value of this newly detected antigen was investigated by enzyme-linked immunosorbent assay (ELISA) in 15 patients with culture-proven infection of prostheses caused by Gram-positive bacteria. The antigen was purified by gel-permeation chromatography from the culture supernatants of coagulase-negative staphylococci grown in a chemically defined medium.

There were significant differences (p < 0.0001) between the serum IgG and IgM levels in patients with infection due to Gram-positive staphylococci and those of a control group of 32 patients with no infection. The ELISA test, which has potential for the diagnosis of infection, may be valuable in distinguishing between staphylococcal infection around prostheses and aseptic loosening.