一次人工股関節置換術後の人工股関節周囲感染症の危険因子

Risk factors for periprosthetic joint infection after primary artificial hip and knee joint replacements.

• Heng Guo
• Chi Xu
• Jiying Chen

抄録

序論:

我々は、症例対照研究を行うことにより、一次人工股関節置換術後の人工関節周囲感染症（PJI）の危険因子を探ることを目的とした。

INTRODUCTION: We aimed to explore the risk factors for periprosthetic joint infection (PJI) after primary artificial hip and knee joint replacements by performing a case-control study.

方法:

一次人工股関節置換術および人工膝関節置換術を受けた患者の臨床データをレトロスペクティブに解析した。症例群には PJI を発症した 96 例の患者が含まれており，その内訳は股関節置換術 42 例と膝関節置換術 54 例であった．また、同時期に1：2の割合で人工関節置換術を受け、PJIを発症しなかった192例を対照群とした。病因、病原体、血液型、尿培養、BMI（body mass index）、手術時間、術中出血、術後1日目と総排液量、入院期間、患部の手術歴について、両群間の違いを比較した。

METHODOLOGY: The clinical data of patients receiving primary hip and knee joint replacements were retrospectively analyzed. The case group included 96 patients who suffered from PJI, comprising 42 cases of hip joint replacement and 54 cases of knee joint replacement. Another 192 patients who received joint replacement at the ratio of 1:2 in the same period and did not suffer from PJI were selected as the control group. Differences between the two groups were compared in regard to etiology, pathogen, blood type, urine culture, body mass index (BMI), surgical time, intraoperative blood loss, postoperative 1st day and total drainage volumes, length of hospitalization stay, and history of surgery at the affected sites.

結果:

PJIの主な病原体はグラム陽性菌であった。股関節置換術後の感染症で最も多かったのはエピダーミディス菌（Staphylococcus epidermidis）で38.10％、膝関節の感染症では黄色ブドウ球菌（Staphylococcus aureus）が主な原因となっていた（40.74％）。高BMI、手術時間の長さ、術後ドレナージ量の多さ、入院期間の長さ、切開部手術歴、免疫抑制剤の使用歴、術前の低蛋白血症、表在性感染症は独立した危険因子であった（p＜0.05）。

RESULTS: Gram-positive bacteria were the main pathogens for PJI. The most common infection after hip joint replacement was caused by Staphylococcus epidermidis, which accounted for 38.10%, while Staphylococcus aureus was mainly responsible for the infection of knee joint (40.74%). High BMI, long surgical time, large postoperative drainage volume, long hospitalization stay, history of surgery at incisions, previous use of immunosuppressants, preoperative hypoproteinemia and superficial infection were independent risk factors (p < 0.05).

結論:

一次人工股関節置換術後のPJIは主にグラム陽性菌によるもので、BMIが高い、手術時間が長い、術後ドレナージ量が多い、入院期間が長い、切開部の手術歴がある、免疫抑制剤の使用歴がある、術前に低蛋白血症がある、表在性感染症があるなどの患者さんは感染しやすいと考えられました。

CONCLUSIONS: PJI after primary replacement was mainly caused by gram-positive bacteria, and patients with high BMI, long surgical time, large postoperative drainage volume, long hospitalization stay, history of surgery at incisions, previous use of immunosuppressants, preoperative hypoproteinemia and superficial infection were more vulnerable.

Copyright (c) 2020 Heng Guo, Chi Xu, Jiying Chen.