Histopathologie und Mikrobiologie bei Gelenkinfekten

Recommendations on diagnosis and antimicrobial treatment of infections after anterior cruciate ligament reconstruction (ACL-R) endorsed by ESSKA and EBJIS

Infection after anterior-cruciate ligament reconstruction (ACL-R) is a rare but devastating complication affecting predominantly young and sportive individuals. A timely and correct diagnosis as well as an optimized management are paramount to circumvent serious sequelae and compromise in life quality. These recommendations are primarily intended for use by infectious disease specialists and microbiologists, but also orthopedic surgeons and other healthcare professionals who care for patients with infections after ACL-R. They are based on evidence mainly originating from observational studies and opinions of experts in the field and cover the management of infections after ACL-R with a special focus on etiology, diagnosis, antimicrobial treatment and prevention. Comprehensive recommendations on prevention, surgical treatment and rehabilitation are presented separately in a document primarily addressing orthopedics professionals.

Dental Apical Inflammation Score (DAIS): Histopathological scoring for the evaluation of the apical inflammatory activity and local bone destruction

OBJECTIVE

The purpose of this study was to evaluate 210 periapical lesions with a newly created Dental Apical Inflammation Score/DAIS with regard to their inflammatory cell infiltration, bone tissue, epithelium, bacteria and foreign material.

STUDY DESIGN

Specimens were obtained from 51 different dental practices over a period of 11 months. These specimens were then sent in for histopathological routine diagnostics.

RESULTS

The DAIS classified 81 cases of Type 1 (acute inflammation = low, chronic inflammation = low), 79 cases of Type 2 (acute inflammation = low, chronic inflammation = high), 46 cases of Type 3 (acute inflammation = high, chronic inflammation = low) and 4 cases of Type 4 (acute inflammation = high, chronic inflammation = high). Bone tissue was found in 141 cases, signs for bacterial osteitis in 49 cases, cyst epithelium in 40 cases and foreign material in 27 cases. In 210 cases, cyst epithelium was evident in 27.2 % of Type 1, 15.2 % of Type 2, 8.7 % of Type 3 and in 50 % of Type 4 (p = .019). The 141 cases containing bone tissue showed signs of bacterial osteitis in 16.1 % of Type 1, 29.8 % of Type 2, 77.8 % of Type 3 and in 100 % of Type 4 (p < .001). In 64 cases, Bacteria was evident in 30 % of Type 1, 25 % of Type 2, 55 % of Type 3 and in 100 % of Type 4 (p = .013).

CONCLUSION

The DAIS could classify apical lesions with statistically significant differences. Bacterial osteitis in apical lesions was reported for the first time.

Three-year follow-up of changes of cortical bone thickness after implantation of Endo-Exo-Prosthesis (EEP) for transfemoral amputees

Introduction

Transcutaneous Osseointegrated Prosthetic Systems (TOPS) offer a good alternative for patients who cannot be satisfactorily rehabilitated by conventional suspension sockets. The Endo-Exo-Prothesis (EEP, ESKA Orthopaedic Handels GmbH®, Deutschland) is the most implanted TOPS in Germany. Previous studies have shown that cortical thickness increases after implantation of TOPS. The aim of this study is to determine changes of cortical thickness in relation to the time after implantation of the Endo-Fix-Stem.

Patients and methods

All transfemoral amputees treated by EEP from 2007 to 2013 were operated by the last author of this study. X-ray images of 4 follow-up intervals (postoperative, 3 months, 12 months, 3 years) were analyzed retrospectively. The femoral residuum was divided into 3 sections (proximal, middle, distal) with 2 measuring points in each section: medial and lateral. Cortical thickness was measured at these 6 points and compared at regular intervals using the Friedman test for non-parametric dependent variables.

Results

Thirty-seven patients with 40 implants were included. The average age was 52.2 years (30–79 years). 83.7% of the patients were male. No statistical significance could be shown for any of the measuring points of the femoral residual (proximal medial, proximal lateral, middle medial, middle lateral, distal medial, distal lateral) among the mean values of the cortical thickness at the different follow-up times (p > 0.05 for all measuring points). Cortical remodeling processes (> 1 millimeter (mm)) occurred in all implants despite a missing statistical significance. Hypertrophy could be confirmed for 42.5% and atrophy for 37.5%. Twenty percent of the cases showed a parallel occurrence of both entities. Cortical changes greater than 5 mm were only observed at the distal end of the femur.

Conclusion

Even if our results did not show any significant difference, it can be deduced that the osseointegration process leads to a remodeling of the bone structure, both in terms of increased bone formation and bone resorption. However, it has not yet been conclusively clarified which processes lead to hyper- or atrophy. The force transmission between prosthesis and bone and the facultative bacterial colonization of the stoma are still the main factors which may be responsible for the bone remodeling processes.

[Histopathological classification principles of rheumatic joint diseases : Contribution of pathology to the diagnosis]

Even though the diagnostics of rheumatic joint diseases are mostly based on clinical, immunoserological and imaging criteria, histopathology can also make a significant contribution. This is particularly true for clinically unclear monoarticular and periarticular diseases. The contribution of histopathology to the diagnosis of rheumatic diseases is manifold since the histopathological differential diagnosis includes the complete spectrum of synovial diseases. This heterogeneous pathogenetic spectrum is described in the joint pathology algorithm, which includes inflammatory and non-inflammatory diseases. To the latter group belong certain benign tumors such as the diffuse variant of the tenosynovial giant cell tumor, lipoma, hemangioma, vascular malformations and synovial chondromatosis. Additionally, the rare group of storage diseases should be kept in mind. Inflammatory diseases can be discriminated into crystal-induced arthropathies mainly such as gout and pseudogout, into granulomatous diseases such as tuberculosis and foreign-body inoculations, and finally into the large group of non-granulomatous, non-infectious synovitis. This large group is by far the most common, and it often causes difficulties in assigning the histopathological findings to a concrete rheumatologic diagnosis. In this context the synovitis score should be applied as a diagnostic device in these cases, leading to the diagnosis of a low-grade synovitis (which is associated with degenerative arthropathies) or of a high-grade synovitis (associated with rheumatic diseases). Identification of crystals and crystal-like deposits should be carried out with the application of the joint particle algorithm which addresses the identification of endogenous and non-endogenous particle deposits in the synovial tissues. Additionally, the synovitis-score may be used for evaluation of arthritis-progresssion and for the evaluation of inflammation-regression as a consequence of therapy with biologicals.

Assay of Blood and Synovial Fluid of Patients With Rheumatoid Arthritis for Staphylococcus aureus Enterotoxin D: Absence of Bacteria But Presence of Its Toxin

Background:

Rheumatoid arthritis (RA) is the most common chronic inflammatory disease. The staphylococcal superantigens are considered as the causative agent of RA disease.

Objectives:

This study aimed to assess the presence of staphylococcal enterotoxin D in synovial fluid and blood of patients with RA.

Patients and Methods:

A total of 120 blood and SF samples of patients with RA were studied. Bacterial culture, primer pairs design, polymerase chain reaction (PCR), and enzyme-linked immunosorbent assay (ELISA) methods have been used to assess of the staphylococcal enterotoxin D. The data were analyzed through descriptive statistics.

Results:

During this study and after sequential subcultures, only 5 bacterial strains were isolated. The results of PCR showed the presence of staphylococcal enterotoxin D gene in almost 50% of SF and also in 48.4% of blood samples of patients with RA. Similarly, the ELISA method detected staphylococcal enterotoxin D in 36.16% of SF and in 33.33% of blood of patients with RA.

Conclusions:

The result of this study showed that a high percentage of patients with RA have shown staphylococcal enterotoxin D (superantigen D) or entD gene in SF and in blood. However, the origin of this superantigen was not clarified and no Staphylococcus aureus enterotoxin D producer was isolated. This finding indicates other role of this superantigen besides its intoxication. Therefore, staphylococcal enterotoxin D as a biomarker may provide a good model for the diagnosis and treatment of patients with RA.

[Revision arthroplasty : Histopathological diagnostics in periprosthetic joint infections]

BACKGROUND

Histopathological differences in synovia and synovial-like interface membrane (SLIM) patterns can be used to differentiate periprosthetic particle-induced reactions, bacterial infections (bacterial synovitis and osteomyelitis), mechanical-induced tissue alterations, adverse reactions to implant material, and arthrofibrosis (SLIM consensus classification).

AIM

Because of differences in treatment the diagnosis of a bacterial implant infection is very important. Histopathological tests and scoring systems are important diagnostic tools in identifying deep implant infections in patients with unclear clinical history as well as radiographic and laboratory studies.

RESULTS

Modern enzyme PCR-based methods, histochemical- and immune-histopathological techniques (CD3,CD15, CD68) are useful in identifying specific and nonspecific infections, as well as differentiating postsurgical changes from recurrent infections in patients with a spacer. In all histopathological scoring systems for bacterial infection, quantifying the number of neutrophil granulocytes in a defined number of high power fields is crucial.

DISCUSSION

Neutrophil granulocytes can be detected through histochemical methods and more specifically by immune-histopathological techniques and by various quantification systems (histopathological scores) leading to the diagnosis of bacterial peri-implant infection. One important function of histopathology, apart from diagnosing infection, is to rule out other mechanisms of implant failure, such as tumor infiltrations, particle-induced reactions, and adverse reactions to implant materials.

Histopathological Osteomyelitis Evaluation Score (HOES) - an innovative approach to histopathological diagnostics and scoring of osteomyelitis

BACKGROUND

Treatment and diagnosis of osteomyelitis are still a challenging problem for surgeons, microbiologists and histopathologists. A direct microbiological detection of bacteria in tissues is still gold standard, but it is not always successful for example in chronic osteomyelitis and/or when an antibiotic treatment has already been started or in cases of low virulent bacteria. The goal of this study was to define diagnostic criteria of osteomyelitis, the inflammatory regression of osteomyelitis ("osteomyelitis score") under specific therapy by the correlation of histopathological and microbiological and clinical standard tests.

METHODS

In this retrospective analysis patients with medical history and clinically clear signs of bacterial infection and osteomyelitis underwent surgery between 01.01.2013 and 31.12.2012. Their formal consent was given. Tissue samples were taken during surgery according to defined criteria including surgical interventions. Histopathological diagnosis was carried out by conventional techniques based on defined criteria of bacterial infection in connective tissue, peri-implant membrane and bone. These results were carried out in tables by numbers representing the histopathological criteria of acute osteomyelitis (A1 to A3) as well as the chronic criteria (C1 and C2) in a semiquantitative way (scale 0 to 3). On the other hand a notational, graduated histopathological report was performed. Preoperative clinical diagnosis, perioperative macroscopic diagnosis, histopathological and microbiological findings were correlated.

RESULTS

Histopathological samples of 52 surgical interventions based on the preoperative diagnosis "osteomyelitis" (AOM, ECOM or COM) were included. 37 times preoperatively signs of a chronic osteomyelitis (COM), 10 times preoperatively acute osteomyelitis (AOM) was diagnosed. Another 5 patients were preoperatively diagnosed as acute exacerbated osteomyelitis (ECOM). The correlation of the histopathological infection including the inflammatory activity and microbiological detection of bacteria was 57%. The correlation between preoperative diagnosis and histopathological findings was 68%.

CONCLUSION

The relatively small 68% correlation between clinical preoperative and histopathological diagnosis and 57% correlation between preoperative clinical diagnosis and microbiological findings indicates: Clinical findings are not sufficient for the diagnosis "osteomyelitis".Clinical findings are not sufficient for the differentiation between AOM, ECOM and COM.Histopathological analysis is the critical factor for the diagnosis ("osteomyelitis") and differential diagnosis (AOM vs. COM).Histopathological analysis represents the basis for further treatment.HOES facilitates the classification of the histopathological findings.HOES is a sufficient tool for the treating physician in order to define the further treatment.

[Periprosthetic infections in systemic inflammatory rheumatic disease. Review article on diagnostics and therapy]

BACKGROUND

Patients with an inflammatory disease have an elevated risk for periprosthetic joint infections due to impairment of the immune system caused by the disease itself in combination with disease-modifying antirheumatic drugs (DMARD). These infections can cause life-threatening sepsis. Unfortunately recommendations on the diagnostics and treatment are mostly based on studies with a level of evidence grade IV or V.

OBJECTIVES

This article gives an overview of recent publications evaluating the level of evidence of recommendations on diagnostics and treatment of periprosthetic joint infections in patients with inflammatory diseases.

METHODS

A systematic literature search was performed in the Medline database in January and February 2014. The search included all articles on diagnostic and/or treatment of periprosthetic joint infections in patients with inflammatory diseases. Articles in languages other than English or German were excluded, as well as case reports, studies with less than 20 patients and articles only referring to patients with inflammatory diseases without periprosthetic infections.

RESULTS

Nearly all recommendations are based on retrospective studies or expert opinions (level of evidence IV or V). Conflicting results are common but there is good evidence on preoperative aspiration of joint fluid (level of evidence I) and a doubled risk of joint infections under treatment with anti-tumor necrosis factor (level of evidence II). An increased mortality has been reported in multiple studies. Two-stage revision seems to have a slightly better outcome than retention of prosthesis or one-stage revision. Generally, therapeutic recommendations for periprosthetic joint infections lack a good level of evidence. Future studies are urgently needed.