Table 2. Patient-related medical risk factors for periprosthetic joint infection.

Risk factor	Link to PJI	Intervention	Goal
Morbid obesity	Prolonged operative time, increased risk of poor wound healing, paradoxical malnutrition, presence of other medical comorbidities	Diet and exercise, bariatric surgery	BMI ≤40 kg/m2
Malnutrition	Poor wound healing and persistent wound drainage	Administration of protein, vitamin and mineral supplementation; increased caloric intake	Serum albumin levels ≥3.5 g/dL; Serum transferrin levels ≥200 mg/dL; Serum prealbumin levels ≥15 mg/dL; TLC ≥1,500 cells/mm3
Hyperglycemia and uncontrolled diabetes mellitus	Advanced glycation end products, decreased bacterial defenses	Diet and exercise, insulin	HgbA1c ≤8%, blood glucose ≤200 mg/dL
Rheumatoid arthritis	Immunosuppressive therapies (corticosteroids and DMARDs), increased rate of surgical wound complications, presence of other medical comorbidities	Perioperative cessation of immunosuppressive therapies
Preoperative anemia	Increased need for allogeneic blood transfusions	Preoperatively screen for other possible causes of anemia (i.e. iron deficiency), preoperative administration of recombinant human erythropoietin	Hgb ≥12 g/dL in women and 13 g/dL in men
Cardiovascular disorder	Chronic anticoagulation therapy and increased INR; increased risk of would related complications and poor wound healing	Perioperative cessation of anticoagulation therapy, preoperative evaluation by cardiologist	INR level ≤2
Chronic renal failure	Presence of other medical comorbidities, immunosuppressive nature of therapy (hemodialysis and renal transplantation)	Preoperative evaluation of patient by nephrologist, postoperative management of renal function
Smoking	Hypoperfusion, platelet aggregation and formation of thrombi, wound hypoxia, poor wound healing, decreased immune defenses	Preoperative evaluation of smoking history, perioperative smoking cessation, individual counseling, physician advising, NTR
Alcohol abuse	Protein deficiency and malnutrition, diminished host immunity, impaired wound healing	Preoperative evaluation of alcohol history, perioperative alcohol cessation
Depression	Presence of other medical comorbidities (i.e., malnutrition and need for allogeneic blood transfusion); immunomodulatory effects	Evaluation of depression during preoperative medical screening, treatment of depression prior to surgery

PJI, periprosthetic joint infection; BMI, body mass index; DMARD, disease-modifying anti-rheumatic drugs; Hgb, hemoglobin; INR, international normalized ratio; TLC, total lymphocyte count; NTR, nicotine replacement therapy.