Background
Methods
Study population
Definition of clinical variables
Variable | Definition |
---|---|
Diabetes mellitus | The diagnosis is based on one of four abnormalities outlined by American Diabetes Association, 2010: glycated hemoglobin (A1C) ≥6.5 %, fasting plasma glucose (FPG) ≥126 mg/dl, random plasma glucose ≥200 mg/dl with symptoms, or two-hour plasma glucose ≥200 mg/dl during an oral glucose tolerance test (OGTT) |
Functional status | Patient requiring no, partial or totally dependent assistance from another person for activities of daily living before surgery |
Hypertension | Patient with elevated blood pressure requiring medication |
Chronic renal failure | Patient with a rising creatinine >3 mg/dl or a decreased glomerular filtration rate of less than 60 ml/min/1.73 m2 for 3 or more months |
Liver cirrhosis | Diagnosis based on clinical, laboratory and echographic findings |
SIRS | Includes the presence of two or more of the following: temperature >38 °C or <36 °C, heart rate >90 bpm, respiratory rate >20 breaths/min or PaCO2 < 32 mm/Hg, WBC >12,000/mm3 or <4000/mm3, or >10 % immature (band) forms, anion gap acidosis |
Septic shock | Includes sepsis and documented organ and/or circulatory dysfunction |
ASA score | 1 = normal healthy patient |
2 = patient with mild systemic disease | |
3 = patient with severe systemic disease | |
4 = patient with severe systemic disease that is a constant threat to life | |
5 = moribund patient who is not expected to survive without the operation | |
Limb loss | Amputation of the lower or upper limb above the ankle or the wrist, respectively. |
Treatment protocol
Collection of clinical data
Statistical analysis
Results
General clinical characteristics
Comparison of diabetic and nondiabetic NF patients
NF type, Causative pathogen(s) | All patients, n (%) | DM, n (%) | Non-DM, n (%) | P value (DM vs non-DM) |
---|---|---|---|---|
Monomicrobial | ||||
Group A Streptococcus | 12 (7.3) | 3 (3.6) | 9 (11.1) | 0.076 |
Group B Streptococcus | 4 (2.4) | 2 (2.4) | 2 (2.5) | 1.0 |
Staphyloccocus aureus | ||||
MRSA | 14 (8.5) | 6 (7.1) | 8 (9.9) | 0.529 |
MSSA | 12 (7.3) | 5 (6.0) | 7 (8.6) | 0.561 |
Aeromonas hydrophilia | 7 (4.2) | 2 (2.4) | 5 (6.2) | 0.271 |
Vibrio vulnificus | 9 (5.5) | 4 (4.8) | 5 (6.2) | 0.737 |
Escherichia coli | 10 (6.1) | 4 (4.8) | 6 (7.4) | 0.530 |
Klebsiella pneumoniae | 17 (10.3) | 13 (15.5) | 4 (4.9) | 0.038 |
Pseudomonas aeruginosa | 4 (2.4) | 0 (0) | 4 (4.9) | 0.056 |
Serratia marcescens | 4 (2.4) | 2 (2.4) | 2 (2.5) | 1.0 |
Others | 28 (17.0) | 14 (16.7) | 14 (17.3) | 0.916 |
Polymicrobial | ||||
Mixed infection | 30 (18.2) | 22 (26.2) | 8 (9.9) | 0.007 |
Culture negative | ||||
No bacterial growth | 14 (8.5) | 7 (8.3) | 7 (8.6) | 0.943 |
Total | 165 | 84 | 81 |
Variable | DM (n = 84) | Non-DM (n = 81) | P value |
---|---|---|---|
Age | 61.5 ± 10.6 | 56 ± 22.2 | 0.045 |
Male gender | 58(69.1) | 52(64.2) | 0.509 |
American Society of Anaesthesiologists (ASA) score | |||
1 | 4(4.8) | 14(17.3) | 0.079 |
2 | 23(27.4) | 20(24.7) | |
3 | 37(44.0) | 32(39.5) | |
4 | 20(23.8) | 15(18.5) | |
Pre-existing medical conditions | |||
Hypertension | 35(42.2) | 24(29.6) | 0.094 |
Chronic renal failure | 19(22.6) | 10(12.4) | 0.083 |
Liver cirrhosis | 12(14.3) | 10(12.4) | 0.714 |
Malignancy | 6(7.1) | 8(9.9) | 0.529 |
Immunosuppresant medication | 7(8.3) | 8(9.9) | 0.730 |
Admission lab data | |||
Hemoglobin (mg/dl) | 10.4 ± 2.5 | 10.8 ± 2.5 | 0.321 |
Leukocyte count (103/mm3) | 11.1 ± 9.9 | 10.5 ± 11.8 | 0.767 |
Platelet count (103/mm3) | 188.8 ± 129.5 | 160.7 ± 109.3 | 0.167 |
C-reactive protein > 10 mg/dla | 43(75.4) | 44(83.0) | 0.329 |
Glucose > 110 mg/dlb | 41(85.4) | 17(48.6) | <0.001 |
Potassium (mEq/l) | 4.4 ± 1.1 | 4.0 ± 0.8 | 0.010 |
Positive blood culturec | 28(41.8) | 27(49.1) | 0.420 |
Location of infection | |||
body | 10(11.9) | 11(13.6) | 0.651 |
head and neck | 3(3.6) | 1(1.2) | |
upper limb | 9(10.7) | 8(9.9) | |
lower limb | 54(64.3) | 57(70.4) | |
multiple sites | 8(9.5) | 4(4.9) | |
Time to surgery <12 h | 43(51.2) | 44(54.3) | 0.687 |
ICU stay (day) | 9.3 ± 10.8 | 9.8 ± 12.1 | 0.793 |
Hospital stay (day) | 39.1 ± 28.6 | 41.1 ± 38.4 | 0.712 |
Limb loss | 24(28.6) | 11(13.6) | 0.019 |
Mortality | 24(28.6) | 25(30.9) | 0.747 |
Risk factors for mortality
Variable | Survivors (n = 116) | Non-survivors (n = 49) | P value |
---|---|---|---|
Age | 57.8 ± 17.9 | 61 ± 16.4 | 0.297 |
Male gender | 75(64.7) | 35(71.4) | 0.399 |
American Society of Anaesthesiologists (ASA) score | |||
1 | 13(11.2) | 5(10.2) | 0.268 |
2 | 33(28. 5) | 10(20.4) | |
3 | 50(43.1) | 19(38. 8) | |
4 | 20(17.2) | 15(30.6) | |
Pre-existing medical conditions | |||
Diabetes mellitus | 60(51.7) | 24(49.0) | 0.747 |
Hypertension | 39(33.6) | 20(41. 7) | 0.329 |
Chronic renal failure | 17(14.7) | 12(24.5) | 0.129 |
Liver cirrhosis | 13(11.2) | 9(18.4) | 0.216 |
Malignancy | 10(8.6) | 4(8.2) | 1 |
Immunosuppresant medication | 9(7.8) | 6(12.2) | 0.382 |
Admission lab data | |||
Hemoglobin (mg/dl) | 10.8 ± 2.4 | 10.1 ± 2.6 | 0.135 |
Leukocyte count (103/mm3) | 11.3 ± 11.3 | 9.7 ± 9.9 | 0.3777 |
Platelet count (103/mm3) | 193.7 ± 128.8 | 135.2 ± 89.0 | 0.0021 |
C-reactive protein > 10 mg/dla | 58(79. 5) | 29(78.4) | 0896 |
Glucose > 110 mg/dlb | 39(65) | 19(82.61) | 0.356 |
Potassium (mEq/l) | 4.0 ± 0.9 | 4.5 ± 1.2 | 0.034 |
Positive blood culturec | 33(38.82) | 22(59.46) | 0.035 |
Location of infection | |||
body | 9(7.8) | 12(24.5) | 0.025 |
head and neck | 3(2.6) | 1(2.0) | |
upper limb | 10(8.6) | 7(14.3) | |
lower limb | 84(72.4) | 27(55.1) | |
multiple sites | 10(8.6) | 2(4.1) | |
Time to surgery <12 h | 62(54.39) | 25(54.35) | 0.531 |
ICU stay (day) | 9.5 ± 12.1 | 9.5 ± 10.4 | 0.977 |
Hospital stay (day) | 51.7 ± 33.4 | 13.6 ± 14.4 | <.0001 |
Limb loss | 28(24.1) | 7(14.3) | 0.157 |
Variable | Univariate analysis | Multivariate analysis | ||
---|---|---|---|---|
OR(95 % CI) | P value | OR(95 % CI) | P value | |
Age | 1.01(0.99,1.03) | 0.3 | ||
Male gender | 1.37(0.66,2.83) | 0.4 | ||
Functional status | ||||
Partially dependent | 1 | - | ||
Totally dependent | 0.79(0.25,2.52) | 0.69 | ||
Totally independent | 0.79(0.38,1.61) | 0.51 | ||
Underlying medical conditions | ||||
DM | 0.90(0.46,1.75) | 0.75 | ||
Chronic renal failure | 1.89(0.82,4.33) | 0.13 | ||
Immunosuppresant medication | 1.66(0.56,4.94) | 0.36 | ||
Clinical presentation at admission | ||||
Consciousness disturbance | 1.77(0.88,3.56) | 0.11 | ||
Temperature > 38 °C | 1.58(0.77,3.22) | 0.21 | ||
Dyspnea | 2.68(1.32,5.45) | 0.007 | 2.29(0.81,6.43) | 0.117 |
Systolic BP < 90 mmHg | 2.03(1.02,4.06) | 0.045 | 1.14(0.4,3.2) | 0.810 |
SIRS | 2.08(0.73,5.88) | 0.17 | ||
Pus at infection site | 0.73(0.31,1.68) | 0.45 | ||
Admission lab data | ||||
Hemoglobulin (mg/dl) | 0.90(0.78,1.04) | 0.14 | ||
Leukocyte (103/mm3) | 0.99(0.95,1.02) | 0.38 | ||
Platelet (103/mm3) | 0.995(0.99,0.999) | 0.008 | 1(0.99,1) | 0.056 |
Potassium (mEq/l) | 1.57(1.06,2.31) | 0.023 | 2.2(1.2,4.02) | 0.011 |
Positive blood culture | 2.31(1.05,5.08) | 0.037 | 1.95(0.71,5.38) | 0.197 |
Time to surgery <12 h | 0.83(0.41,1.68) | 0.598 |
Variable | Univariate analysis | Multivariate analysis | ||
---|---|---|---|---|
OR(95 % CI) | P value | OR(95 % CI) | P value | |
Age | 0.98(0.93,1.02) | 0.34 | ||
Male gender | 2.05(0.67,6.26) | 0.21 | ||
Functional status | ||||
Partially dependent | 1 | - | ||
Totally dependent | 2.72(0.5,14.72) | 0.25 | ||
Totally independent | 1.81(0.65,5.07) | 0.26 | ||
Underlying medical conditions | ||||
Chronic renal failure | 1.65(0.56,4.87) | 0.37 | ||
Immunosuppresant medication | 3.80(0.78,18.47) | 0.10 | ||
Clinical presentation at admission | ||||
Consciousness disturbance | 1.69(0.64,4.45) | 0.29 | ||
Temperature > 38 °C | 1.87(0.68,5.18) | 0.23 | ||
Dyspnea | 3.50(1.24,9.89) | 0.018 | 4.19(0.98,17.91) | 0.053 |
Systolic BP < 90 mmHg | 2.89(1.05,7.96) | 0.040 | 1.81(0.45,7.21) | 0.403 |
SIRS | 0.78(0.21,2.88) | 0.70 | ||
Pus at infection site | 1.75(0.59,5.21) | 0.31 | ||
Admission lab data | ||||
Hemoglobulin (mg/dl) | 0.86(0.69,1.06) | 0.16 | ||
Leukocyte (103/mm3) | 1.01(0.96,1.06) | 0.81 | ||
Platelet (103/mm3) | 0.996(0.99,1.001) | 0.13 | ||
Potassium (mEq/l) | 1.84(1.08,3.15) | 0.025 | 1.65(0.84,3.24) | 0.147 |
Positive blood culture | 4.57(1.52,13.78) | 0.007 | 7.36(1.66,32.54) | 0.009 |
Variable | Univariate analysis | Multivariate analysis | ||
---|---|---|---|---|
OR(95 % CI) | P value | OR(95 % CI) | P value | |
Age | 1.02(1.00,1.04) | 0.1 | ||
Male gender | 0.99(0.37,2.64) | 0.98 | ||
Functional status | ||||
Partially dependent | 1 | - | ||
Totally dependent | 0.22(0.04,1.25) | 0.09 | 0.23(0.03,2.09) | 0.193 |
Totally independent | 0.29(0.1,0.85) | 0.025 | 0.16(0.04,0.74) | 0.019 |
Underlying medical conditions | ||||
Chronic renal failure | 2.55(0.67,9.77) | 0.17 | ||
Immunosuppresant medication | 0.73(0.14,3.87) | 0.71 | ||
Clinical presentation at admission | ||||
Consciousness disturbance | 1.97(0.70,5.56) | 0.2 | ||
Temperature > 38 °C | 1.40(0.50,3.90) | 0.52 | ||
Dyspnea | 2.15(0.80,5.76) | 0.13 | ||
Systolic BP < 90 mmHg | 1.45(0.56,3.78) | 0.45 | ||
SIRS | 8.21(1.01,66.85) | 0.049 | 12.21(1.09,137.21) | 0.043 |
Pus at infection site | 0.22(0.05,1.03) | 0.05 | 0.09(0.01,0.86) | 0.037 |
Admission lab data | ||||
Hemoglobulin (mg/dl) | 0.93(0.77,1.13) | 0.45 | ||
Leukocyte (103/mm3) | 0.97(0.93,1.02) | 0.18 | ||
Platelet (103/mm3) | 0.99(0.987,0.999) | 0.021 | 0.997(0.99,1.004) | 0.382 |
Potassium (mEq/l) | 1.39(0.71,2.70) | 0.34 | ||
Positive blood culture | 1.05(0.33,3.37) | 0.93 |