Utility of C-reactive protein measurements for empyema diagnosis after pneumonectomy

Pleural Space Infections

Pleural space infections have been a well-recognized clinical syndrome for over 4000 years and continue to cause significant morbidity and mortality worldwide. However, our collective understanding of the causative pathophysiology has greatly expanded over the last few decades, as have our treatment options. The aim of this paper is to review recent updates in our understanding of this troublesome disease and to provide updates on established and emerging treatment modalities for patients suffering from pleural space infections. With that, we present a review and discussion synthesizing the recent pertinent literature surrounding the history, epidemiology, pathophysiology, diagnosis, and management of these challenging infections.

[Pneumonectomy for Non-small Cell Lung Cancer: Predictors of Operative Mortality and Survival]

外科手术是目前根治非小细胞肺癌（non-small cell lung cancer, NSCLC）的最有效方式。全肺切除作为一种术式被应用于临床中。对于中央型肺癌，袖式肺叶切除术因其术后肺功能丧失少、术后并发症及死亡率低逐渐取代全肺切除术成为主流。然而为保证肿瘤学效果，当其他术式无法完全切除时，全肺切除术式仍是必要的。全肺切除术后主要发生心肺并发症，充分了解全肺切除术后相关并发症能帮助临床医师及时做出诊断，并进一步采取相关措施降低术后并发症对患者的不良影响。充分了解预后相关危险因素可帮助临床医师提前采取措施尽可能规避风险，从而改善患者预后。

Postpneumonectomy empyema: risk factors, prevention, diagnosis, and management

Postpneumonectomy empyema is a collection of pus in the pleural space after removal of the underlying lung. Postpneumonectomy empyema is a serious complication responsible for high rates of morbidity and mortality. Several risk factors for the development of postpneumonectomy empyema have been highlighted in the literature. The association of postpneumonectomy empyema with a bronchopleural fistula increases the rate of mortality by flooding the remaining lung. The management of postpneumonectomy empyema depends on the timing of presentation and the presence or absence of a bronchopleural fistula. The goals of care in the acute period are mainly preservation of the contralateral lung and sterilization of the pleural space, which may take a considerable time. The aims in the late period are closure of the bronchopleural fistula, obliteration of the pleural space, and closure of the chest wall.

α-1-Acid glycoprotein as a biomarker for the early diagnosis and monitoring the prognosis of sepsis

OBJECTIVE

To explore the value of α-1-acid glycoprotein (AGP) for the early diagnostic and prognostic assessment of patients with sepsis.

METHODS

Eighty-five patients with systemic inflammatory response syndrome (SIRS) and 192 patients with sepsis were enrolled. White blood cell counts and serum levels of AGP, C-reactive protein, and procalcitonin were tested on the day of admission to intensive care unit (ICU; day 1) and the following days 3, 5, 7, and 10.

RESULTS

The sepsis group exhibited significantly higher levels of AGP than did the SIRS group on day 1 (P < .05); the area under the curve (AUC) of AGP was 0.869 with a specificity of 0.902 on diagnosis of sepsis. The differences were statistically significant among sepsis subgroups. On prognostic assessment, the areas under the curve of AGP, Sequential Organ Failure Assessment (SOFA) scores, and SOFA + AGP on ICU admission were 0.793, 0.813, and 0.878, respectively. The results of logistic regression showed that the odds ratios of AGP, SOFA, Acute Physiology and Chronic Health Evaluation II, and the length of ICU stay were 1.450, 1.212, 1.673, and 1.130.

CONCLUSIONS

α-1-Acid glycoprotein could distinguish sepsis from SIRS and also be used to effectively assess the severity of sepsis. In addition, combined AGP and SOFA scores had a great predicting value in prognosis of sepsis.

C-reactive protein and lung diseases

C-reactive protein (CRP), a member of the pentraxin family of plasma proteins, is one of the most distinctive acute phase reactants. In response to inflammation, cell damage or tissue injury, plasma level of CRP rapidly and dramatically increases up to 1000-fold, a phenomenon that has been used for years to monitor infections and many destructive/inflammatory conditions. The magnitude of CRP increase usually correlates with the severity of injury or inflammation and reflects an important physiological role of this interesting but still under-investigated protein. It is now generally accepted that CRP is involved in host defense and inflammation. However, the exact function of this protein in health and disease remains unclear. Many studies have demonstrated that in different pathophysiological conditions CRP might be involved in the regulation of lung function and may participate in the pathogenesis of various pulmonary disorders. The fluctuation of CRP concentrations in both alveolar fluid and serum associated with different pulmonary diseases suggests its important role in lung biology. Discussion of the still controversial functions of CRP in lung physiology and diseases is the main focus of this review.

Chest tube tip culture as a predictor of postoperative infection in lung cancer operations

BACKGROUND

Postoperative infection is one of the most frequently observed complications after lung resection and should be addressed in perioperative management. This study evaluated the clinical significance of chest tube tip culture relevant to postoperative infection.

METHODS

From September 2002 to December 2011, 1,438 patients who underwent lung cancer operations in Shizuoka Cancer Center Hospital were evaluated. Postoperative infections, including surgical site infection, postoperative pneumonia, and postoperative empyema without fistula, were defined as those occurring within 30 days of thoracotomy.

RESULTS

Postoperative infections developed in 84 of the 1,438 patients (5.8%), including 42 (2.9%) with surgical site infection, 36 (2.5%) with pneumonia, and 13 (0.9%) with empyema. The sensitivity, specificity, and positive predictive value of chest tube tip culture were 23%, 98%, and 41.3%, respectively. Multivariate analysis demonstrated that the independent risk factors associated with the development of postoperative infections were coexisting diabetes mellitus and positive chest tube tip culture. Positive chest tube tip culture was the only independent risk factor associated with surgical site infection. The independent risk factors associated with postoperative pneumonia were age 70 years or older, coexisting diabetes mellitus, and positive chest tube tip culture. Finally, positive chest tube tip culture was the only independent risk factor associated with postoperative empyema.

CONCLUSIONS

Positive chest tube tip culture strongly predicts postoperative infections in lung cancer surgery and necessitates careful observation in the perioperative period.

Persistent systemic inflammation in chronic critical illness

Chronic critical illness (CCI) is syndrome of neuromuscular weakness, brain dysfunction, malnutrition, endocrinopathies, and symptom distress. Two conceptual themes may be useful in discussing CCI. The first is a clinical roadmap in which a patient suffers an acute critical illness, survives the initial insult, but yet is unable to be liberated from the ventilator. The second framework considers the effect of systemic inflammation and CCI, linking acute CCI risk factors with the common clinical features of CCI. Given the association between common CCI antecedents and inflammation, attempts to control and balance the pro-inflammatory and anti-inflammatory mediators should begin as early as possible and continue throughout the ICU stay. Since surrogate measures such as biomarkers often fail to predict the effect of interventions, the focus should be on the outcomes patients experience. As of now, providing evidence-based, high quality ICU management of patients at risk for CCI appears to be the best strategy of care.

C-reactive protein as a marker of postoperative septic complications

THE AIM OF THE STUDY

was to answer the question whether or not determination of C-reactive protein in patients after serious abdominal surgeries can be prognostic of septic complications.

MATERIAL AND METHODS

36 patients who underwent elective surgeries were included in the study. The patients were included either in the group where no postoperative SIRS developed or in the group where postoperative SIRS did occur. In the seven-day period after the surgery, in 26 patients SIRS was found, and in 10 - sepsis was suspected (according to the ACCP/SCCM definitions). In patients who underwent abdominal surgeries blood concentration of C-reactive protein was determined prior to the surgery (measurement '0'), and then on postoperative days 1, 2, 3, 5 and 7.

RESULTS

The test for two variables (C-reactive protein on postoperative days five and seven) showed statistically significant difference, and for one variable (C-reactive protein on day three) - difference at the limit of significance. Thus, it was found that in the postoperative SIRS group the level of C-reactive protein is higher than in the non-SIRS group.

CONCLUSIONS

Serial measurements of C-reactive protein are useful in the first week after surgery, as they can be prognostic of postoperative septic complications. Such complications can be anticipated if CRP on postoperative day 5 is higher than 1/2 of the maximum CRP concentration on day 2 or day 3, or CRP > 150 mg/L as of postoperative day 3. Unfortunately, the severity of the disease cannot be projected based on C-reactive protein level.

Evaluation of serial C-reactive protein measurements after surgical treatment of pleural empyema

OBJECTIVE

Serial C-reactive protein measurements have been used to diagnose and monitor the response to therapy in patients with pneumonia and other infectious diseases. Nonetheless, the role of C-reactive protein measurement after surgical treatment for pleural empyema is not well defined. The aim of this study is to describe the behavior of C-reactive protein levels after the surgical treatment of pleural empyema and to correlate this parameter with the patient's prognosis.

METHODS

We retrospectively analyzed the records of patients with pleural empyema treated by either chest-tube drainage or surgery from January 2006 to December 2008. C-reactive protein levels were recorded preoperatively and 2 and 7 days postoperatively. The clinical outcome was binary: success or failure (mortality or the need for repeated pleural intervention).

RESULTS

The study group comprised fifty-two patients. The median C-reactive protein values were as follows: 146 mg/L (pre-operative), 134 mg/L (post-operative day 2), and 116 mg/L (post-operative day 7). There was a trend toward a decrease in these values during the first week after surgery, but this difference was only statistically significant on day 7 after surgery. Over the first week after surgery, the C-reactive protein values decreased similarly in both groups (successful and failed treatment). No correlation between the preoperative C-reactive protein level and the clinical outcome was found.

CONCLUSIONS

We observed that, in contrast to other medical conditions, C-reactive protein levels fall slowly during the first postoperative week in patients who have undergone surgical treatment for pleural empyema. No correlation between the perioperative C-reactive protein level and the clinical outcome was observed.

Inflammation and outcome after general thoracic surgery

OBJECTIVE

To determine whether preoperative inflammation predisposes to major postoperative complications (PC) and poor outcome.

METHODS

Prospective data collection of 153 consecutive patients aged 73+/-6 years scheduled for lung resection at a tertiary cancer center. High sensitivity C-reactive protein (CRP) and interleukin (IL)-6 levels were measured before surgery, on arrival to the postanesthesia care unit, and on the first morning after surgery.

RESULTS

PC occurred in 9/153 (5.9%) patients. In comparison to patients without PC, those with PC had a greater history of hypertension (P=0.047), higher frequency of non-steroidal anti-inflammatory drug use (P=0.007) and had a lower preoperative albumin level, 3.75+/-0.65 g/dl versus 4.28+/-0.33 g/dl, P=0.03. Receiver operating characteristic analysis demonstrated a strong association between PC and preoperative CRP (area under the curve of 0.86), albumin (area under the curve of 0.86) and less so for IL-6 (area under the curve of 0.79).

CONCLUSIONS

Markers of inflammation, CRP and IL-6, can help distinguish patients who are at high risk for major PC. These preliminary and novel data suggest that in addition to low albumin, a previously described marker of outcome, systemic inflammation is likely to be important in the pathogenesis of important PC.

Early identification of intensive care unit-acquired infections with daily monitoring of C-reactive protein: a prospective observational study

INTRODUCTION

Manifestations of sepsis are sensitive but are poorly specific of infection. Our aim was to assess the value of daily measurements of C-reactive protein (CRP), temperature and white cell count (WCC) in the early identification of intensive care unit (ICU)-acquired infections.

METHODS

We undertook a prospective observational cohort study (14 month). All patients admitted for > or =72 hours (n = 181) were divided into an infected (n = 35) and a noninfected group (n = 28). Infected patients had a documented ICU-acquired infection and were not receiving antibiotics for at least 5 days before diagnosis. Noninfected patients never received antibiotics and were discharged alive. The progression of CRP, temperature and WCC from day -5 to day 0 (day of infection diagnosis or of ICU discharge) was analyzed. Patients were divided into four patterns of CRP course according to a cutoff value for infection diagnosis of 8.7 mg/dl: pattern A, day 0 CRP >8.7 mg/dl and, in the previous days, at least once below the cutoff; pattern B, CRP always >8.7 mg/dl; pattern C, day 0 CRP < or =8.7 mg/dl and, in the previous days, at least once above the cutoff; and pattern D, CRP always < or =8.7 mg/dl.

RESULTS

CRP and the temperature time-course showed a significant increase in infected patients, whereas in noninfected it remained almost unchanged (P < 0.001 and P < 0.001, respectively). The area under the curve for the maximum daily CRP variation in infection prediction was 0.86 (95% confidence interval: 0.752-0.933). A maximum daily CRP variation >4.1 mg/dl was a good marker of infection prediction (sensitivity 92.1%, specificity 71.4%), and in combination with a CRP concentration >8.7 mg/dl the discriminative power increased even further (sensitivity 92.1%, specificity 82.1%). Infection was diagnosed in 92% and 90% of patients with patterns A and B, respectively, and in only two patients with patterns C and D (P < 0.001).

CONCLUSION

Daily CRP monitoring and the recognition of the CRP pattern could be useful in the prediction of ICU-acquired infections. Patients presenting maximum daily CRP variation >4.1 mg/dl plus a CRP level >8.7 mg/dl had an 88% risk of infection.

Post-pneumonectomy empyema: Current management strategies

Post-pneumonectomy empyema is an uncommon but potentially life-threatening complication. It has a strong association with bronchopleural fistula, which acts as a continued source of infection into the thoracic cavity. Numerous risk factors have been identified and strategies formulated to minimize its occurrence. When bronchopleural fistula occurs, its treatment depends on several factors including extent of dehiscence, degree of pleural contamination and general condition of the patient. Early diagnosis and assessment with appropriate investigations, and aggressive therapeutic strategies are paramount in controlling sepsis, facilitating closure of fistula, and sterilization of the closed pleural space. Recent success with repeat debridement has made routine space obliteration not mandatory in management. The development of minimal-access interventions including video-assisted thoracic surgery, endoscopic application of tissue glue and stenting may be additional tools to complement conventional surgery in post-pneumonectomy empyema management.

Serum procalcitonin and C-reactive protein levels as markers of bacterial infection: a systematic review and meta-analysis

A meta-analysis was performed to evaluate the accuracy of determination of procalcitonin (PCT) and C-reactive protein (CRP) levels for the diagnosis of bacterial infection. The analysis included published studies that evaluated these markers for the diagnosis of bacterial infections in hospitalized patients. PCT level was more sensitive (88% [95% confidence interval [CI], 80%-93%] vs. 75% [95% CI, 62%-84%]) and more specific (81% [95% CI, 67%-90%] vs. 67% [95% CI, 56%-77%]) than CRP level for differentiating bacterial from noninfective causes of inflammation. The Q value for PCT markers was higher (0.82 vs. 0.73). The sensitivity for differentiating bacterial from viral infections was also higher for PCT markers (92% [95% CI, 86%-95%] vs. 86% [95% CI, 65%-95%]); the specificities were comparable (73% [95% CI, 42%-91%] vs. 70% [95% CI, 19%-96%]). The Q value was higher for PCT markers (0.89 vs. 0.83). PCT markers also had a higher positive likelihood ratio and lower negative likelihood ratio than did CRP markers in both groups. On the basis of this analysis, the diagnostic accuracy of PCT markers was higher than that of CRP markers among patients hospitalized for suspected bacterial infections.

A new method for detection of postpneumonectomy broncho-pleural fistulas

Broncho-pleural fistula is a relatively rare but life-threatening complication of pneumonectomy. Early detection of this complication is crucial for optimal treatment. We describe a simple technique to detect postpneumonectomy broncho-pleural fistula by measuring concentrations of O2 and N2O in the pneumonectomy cavity at baseline and after allowing patients to breath gas mixtures enriched with O2, N2O, or both. The technique was used in 22 patients. In 20 control patients the test was carried out 48 hours after pneumonectomy. Both the O2 and the N2O test were negative in all cases. However, in 2 patients with broncho-pleural fistula both the O2 and the N2O tests were positive.

Postpneumonectomy empyema

Empyema is a serious complication after pneumonectomy. It is often associated with a bronchopleural fistula. Several risk factors have been associated with an increased incidence of these two challenging complications. Therapy aims at simultaneously treating the infected pleural space and the fistula. The authors describe their favorite methods which include repeated open debridements of the pleural space, primary closure of the fistula, and covering of the bronchial stump using intrathoracic transposition of extrathoracic skeletal muscle followed by delayed closure of the chest wall after instillation of an antibiotic solution (Clagett and modified Clagett procedures). The goals of treatment remain a healthy patient with a healed chest wall and no evidence of drainage or infection. Excellent results can be obtained in more than 80% of patients. Failure is often associated with a persistent or recurrent bronchopleural fistula.

Vacuum-assisted closure therapy guided by C-reactive protein level in patients with deep sternal wound infection

BACKGROUND

Deep sternal wound infection is a serious and potentially lethal complication of cardiac surgery when performed through a median sternotomy. We describe the outcome of a new treatment strategy with C-reactive protein level-guided vacuum-assisted closure used at our department.

METHODS

Data from 16 consecutive adult patients who had deep sternal wound infections after cardiac surgery were reviewed. Patients with superficial infection or sterile dehiscence were not included. All patients with postoperative deep sternal wound infections were treated with first-line vacuum-assisted closure therapy, followed by direct surgical closure. A purpose-built vacuum-assisted closure system consisting of polyurethane foam pieces and a special pump unit was used. The foam was placed in the wound after debridement of foreign material and necrotic tissue. The wound was covered with adhesive drape and connected to the pump unit, which was programmed to create a continuous negative pressure of 125 mm Hg in the wound cavity. Intravenous antibiotics were given according to tissue-culture results. The patients were immediately extubated after the operation. When ingrowth of granulation tissue was observed in all parts of the wound and the plasma C-reactive protein level showed a steady decline to 30 to 70 mg/L or less without confounding factors, such as tissue injuries or concomitant infections, the sternotomy was rewired, and the wound was closed.

RESULTS

All patients were alive and free from deep sternal wound infection 3 months after the operation. The median vacuum-assisted closure treatment time until surgical closure was 9 days (range, 3-34 days), and the median C-reactive protein level at closure was 45 mg/L (range, 20-173 mg/L). The median hospital stay was 22 days (range, 12-120 days).

CONCLUSIONS

Early vacuum-assisted closure treatment, followed by surgical closure guided by the plasma C-reactive protein level, is a reliable and easily applied new strategy in patients with postoperative deep sternal wound infection.

Management of postpneumonectomy empyema and bronchopleural fistula

Empyema after pneumonectomy is often associated with a bronchopleural fistula (BDF) and has a significant mortality. Management options include systemic antibiotics and observation, adequate pleural drainage, appropriate parenteral antibiotics, removal of necrotic tissue, and obliteration of residual pleural space. We prefer to treat the empyema with the procedure originally described by Clagett and Geraci in 1963. They demonstrated that postpneumonectomy empyema could be successfully treated by open pleural drainage, frequent wet-to-dry dressing changes, and when the thorax was clean, secondary chest wall closure with obliteration of the pleural cavity with an antibiotic solution. Failure was most often caused by a persistent or recurrent fistula. Because of this, when a BPF is present, the original Clagett technique was modified to include transposition of a well-vascularized muscle to cover the stump at the time of open drainage to prevent further ischemia and necrosis. Our preference is intrathoracic transposition of extrathoracic skeletal muscle. The goals of therapy for postpneumonectomy empyema remain a healthy patient with a a healed chest wall and no evidence of drainage or infection. Excellent results can be obtained in more than 80% of patients by using the Clagett procedure and intrathoracic muscle transposition when a BPF is present.

[Postpneumonectomy thoracic empyema and dosimetric CT scan. Report of two cases and review of the literature]

Following a pneumonectomy for cancer, the patients are classically observed by clinical examination and standard chest X-ray. However, torpid empyemas can be missed when they occur after the period of hospitalization and when they are not accompanied by a fever. At the time of postoperative radiotherapy, the dosimetric CT scan constitutes the first examination providing objective information of the endothoracic content. It is therefore necessary on this occasion to assure the normality of the postpneumonectomy pleural space while checking that the substituted liquid is homogeneous and above all that the internal mediastinal part of the cavity has a concave appearance. If that is not the case, an empyema should be suspected. The diagnosis, confirmed by a cytobacteriological examination of the pleural fluid, constitutes a counterindication of the radiotherapy. We present two cases of postpneumonectomy paucisymptomatic empyema which were diagnosed during the course of postoperative radiotherapy when the initial dosimetric CT scan was pathologic and could have allowed an earlier diagnosis.

Surgical management of empyema

The cause and presentation of empyema thoraces has changed little since it was first described. The natural history of the disease can be divided into different stages. Different therapeutic measures, medical and surgical, are available for the treatment at various stages. The management of empyema is discussed, emphasizing the surgical aspects.

Value of C-reactive protein in the detection of bacterial contamination at the time of presentation in drug-induced aspiration pneumonia

STUDY OBJECTIVES

To compare the plasma concentration of C-reactive protein (CRP) with traditional markers for diagnosis of bacterial pneumonia in patients with suspected aspiration.

DESIGN

Prospective, nonrandomized, controlled study of consecutive hospital admissions.

SETTING

Toxicology ICU in a university hospital.

PATIENTS OR PARTICIPANTS

Acutely poisoned comatose patients admitted to the hospital with suspicion of aspiration pneumonia.

INTERVENTIONS

Distal protected catheter sampling per fiberoptic bronchoscopy and bacteriologic culture were employed as a standard to detect the bacterial component of suspected aspiration pneumonia. Plasma CRP concentrations, temperature, and WBC count were measured on hospital day 1.

MEASUREMENTS AND RESULTS

Sixty-six patients were evaluated. Thirty-two had bacterial contamination by positive culture (> or =10(3) cfu/mL). Multiple receiver-operating characteristic (ROC) curves were used to compare each parameter for detection of infection secondary to aspiration. The ROC curve of CRP concentrations showed that a CRP >75 mg/L is associated with bacterial contamination with a sensitivity of 87%, specificity of 76%, positive predictive value of 78%, and negative predictive value of 87%. ROC curves of temperature and WBC count demonstrated poor diagnostic value of these markers in indicating the bacterial component of suspected aspiration pneumonia.

CONCLUSIONS

Early measurement of CRP is useful for the diagnosis of aerobic bacterial content of aspiration pneumonia and perhaps in determining the need for invasive bacteriologic sampling. Temperature and WBC count are poor indicators of bacterial infection of aspiration pneumonia in poisoned patients.

Short course antimicrobial therapy in intracranial abscess

In this study, the author attempts to question the necessity of prolonged antimicrobial treatment for intracranial abscess. The C reactive protein (CRP) was measured serially in 26 patients with intracranial abscess. All patients had undergone surgery and were treated with antimicrobial therapy. The CRP was elevated in 20 (77%) patients and its return to normal after treatment correlated with a good recovery. In 3 (12%) patients a persistently high CRP level postoperatively coincided with reformation of the abscess. A transient rise in the CRP value during decrease to normal was due to deep venous thrombosis in 2 (8%) patients. The return of the CRP to normal in conjunction with improvement of the patient's clinical condition and evidence of resolution of the abscess on CT scan were used as a guideline to stop antibiotics early. The antimicrobial therapy of the patients in this series ranged from 11-30 (mean 20) days and the follow up from 6-36 (median 21) months; there have been no recurrences.

C-reactive protein for the evaluation of acute abdominal pain

The diagnostic value of C-reactive protein (CRP) was established in 143 patients with acute abdominal pain, 67 men and 76 women with mean age of 48 +/- 20 years old. Clinical and laboratory variables were collected after the patients' arrival at the emergency department. The attending clinicians did not consider the CRP value during the study period and did not use it for their management. When patients were grouped by final disposition, which was according to severity, only CRP and leukocyte count were identified as significant quantitative variables by multivariate analysis. CRP can detect the serious conditions, ie, in 79% of the hospitalized group, although specificity was 64%, the total accuracy was 73%. When elevated CRP was combined with leukocytosis, the diagnostic value was much improved, with specificity of 89% and positive predictive value of 88%. The sensitivity was improved to 90% when elevated CRP or leukocytosis was used. It is thus concluded that CRP is a helpful quantitative variable for disposition decision-making in patients with acute abdominal pain.