Case report of parapneumonic effusion and mesothelial subdiaphragmatic cyst: relationship or coincidence?

Parapneumonic pleural effusions are common in patients with pneumonia. When colonized by pathogenic bacteria or other microorganisms, these effusions can progress to empyema. Additionally, empyema formation may result in extension of the infection into the infradiaphragmatic region, further complicating the clinical scenario. Many subphrenic collections are found to be mesothelial cysts, which are congenital in origin. However, data regarding the potential association between mesothelial diaphragmatic cysts and parapneumonic effusions are limited. We herein describe a toddler with pneumonia complicated by parapneumonic effusion and a lung abscess with a subphrenic collection. After abscess drainage and a full course of antibiotics, imaging revealed clear lung parenchyma with an interval resolution of the effusion and a persistent unchanged subphrenic collection that was confirmed to be mesothelial diaphragmatic cyst. This case highlights the fact that not every subphrenic collection associated with parapneumonic effusion is a communicated collection formed by seeding. Such a collection can instead be an incidental cyst, which is congenital in origin and known as a mesothelial diaphragmatic cyst. A diaphragmatic mesothelial cyst is an uncommon benign congenital cyst that is unrelated to an adjacent parapneumonic effusion. It is usually incidental and can be monitored without invasive intervention.

The importance of the bacterial spectrum in the clinical diagnostics and management of patients with spontaneous pyogenic spondylodiscitis and isolated spinal epidural empyema: a 20-year cohort study at a single spine center.

BACKGROUND: Personalized clinical management of spondylodiscitis (SD) and isolated spinal epidural empyema (ISEE) is challenging due to limited evidence of microbiologic findings and their clinical impact during the clinical course of the disease. We aimed to characterize clinico-microbiological and imaging phenotypes of SD and ISEE to provide useful insights that could improve outcomes and potentially modify guidelines. METHODS: We performed chart review and collected data on the following parameters: bacterial antibiogram-resistogram, type of primary spinal infection, location of spinal infection, source of infection, method of detection, clinical complications (sepsis, septic embolism, and endocarditis), length of hospital and intensive care unit (ICU) stay, relapse rate, and disease-related mortality in patients with proven pyogenic SD and ISEE treated surgically in a university hospital in Germany between 2002 and 2022. RESULTS: We included data from 187 patients (125 SD, 66.8% and 62 ISEE, 33.2%). Gram-positive bacteria (GPB) were overall more frequently detected than gram-negative bacteria (GNB) (GPB: 162, 86.6% vs. GNB: 25, 13.4%, p < 0.001). Infective endocarditis was caused only by GPB (GPB: 23, 16.5% vs. GNB: 0, 0.0%, p = 0.046). Methicillin-susceptible Staphylococcus aureus was the most frequently isolated strain (MSSA: n = 100, 53.5%), occurred more frequently in the cervical spine compared to other bacteria (OB) (MSSA: 41, 41.0% vs. OB: 18, 20.7%, p = 0.004) and was most frequently detected in patients with skin infection as the primary source of infection (MSSA: 26, 40.6% vs. OB: 11, 16.7%, p = 0.002). Streptococcus spp. and Enterococcus spp. (SE: n = 31, 16.6%) were more often regarded as the cause of endocarditis (SE: 8, 27.6% vs. OB: 15, 11.4%, p = 0.037) and were less frequently detected in intraoperative specimens (SE: 19, 61.3% vs. OB: 138, 88.5%, p < 0.001). Enterobacterales (E: n = 20, 10.7%) were identified more frequently in urinary tract infections (E: 9, 50.0% vs. OB: 4, 3.6%, p < 0.001). Coagulase-negative Staphylococci (CoNS: n = 20, 10.7%) were characterized by a lower prevalence of sepsis (CoNS: 4, 20.0% vs. OB: 90, 53.9%, p = 0.004) and were more frequently detected in intraoperative specimens (CoNS: 20, 100. 0% vs. OB: 137, 82.0%, p = 0.048). Moreover, CoNS-associated cases showed a shorter length of ICU stay (CoNS: 2 [1-18] days vs. OB: 6 [1-53] days, median [interquartile range], p = 0.037), and occurred more frequently due to foreign body-associated infections (CoNS: 8, 61.5% vs. OB: 15, 12.8%, p = 0.008). The presence of methicillin-resistant Staphylococcus aureus (MRSA) prolonged hospital stay by 56 [24-58] days and ICU stay by 16 [1-44] days, whereas patients with Pseudomonas aeruginosa spent only 20 [18-29] days in the hospital and no day in the ICU 0 [0-5] days. CONCLUSIONS: Our retrospective cohort study identified distinct bacterial-specific manifestations in pyogenic SD and ISEE regarding clinical course, neuroanatomic targets, method of pathogen detection, and sources of infection. The clinico-microbiological patterns varied depending on the specific pathogens.

Value of preoperative evaluation of FEV1 in patients with destroyed lung undergoing pneumonectomy - a 20-year real-world study.

BACKGROUND: Clinical guidelines recommend a preoperative forced expiratory volume in one second (FEV1) of > 2 L as an indication for left or right pneumonectomy. This study compares the safety and long-term prognosis of pneumonectomy for destroyed lung (DL) patients with FEV1 ≤ 2 L or > 2 L. METHODS: A total of 123 DL patients who underwent pneumonectomy between November 2002 and February 2023 at the Department of Thoracic Surgery, Beijing Chest Hospital were included. Patients were sorted into two groups: the FEV1 > 2 L group (n = 30) or the FEV1 ≤ 2 L group (n = 96). Clinical characteristics and rates of mortality, complications within 30 days after surgery, long-term mortality, occurrence of residual lung infection/tuberculosis (TB), bronchopleural fistula/empyema, readmission by last follow-up visit, and modified Medical Research Council (mMRC) dyspnea scores were compared between groups. RESULTS: A total of 96.7% (119/123) of patients were successfully discharged, with 75.6% (93/123) in the FEV1 ≤ 2 L group. As compared to the FEV1 > 2 L group, the FEV1 ≤ 2 L group exhibited significantly lower proportions of males, patients with smoking histories, patients with lung cavities as revealed by chest imaging findings, and patients with lower forced vital capacity as a percentage of predicted values (FVC%pred) (P values of 0.001, 0.027, and 0.023, 0.003, respectively). No significant intergroup differences were observed in rates of mortality within 30 days after surgery, incidence of postoperative complications, long-term mortality, occurrence of residual lung infection/TB, bronchopleural fistula/empyema, mMRC ≥ 1 at the last follow-up visit, and postoperative readmission (P > 0.05). CONCLUSIONS: As most DL patients planning to undergo left/right pneumonectomy have a preoperative FEV1 ≤ 2 L, the procedure is generally safe with favourable short- and long-term prognoses for these patients. Consequently, the results of this study suggest that DL patient preoperative FEV1 > 2 L should not be utilised as an exclusion criterion for pneumonectomy.

Pharyngo-cervicospinal fistula with destructive osteomyelitis after laryngopharyngectomy and radiotherapy, managed successfully with a vascularized fibula free flap.

Total laryngectomy is an operation mainly employed in recurrent laryngeal and hypopharyngeal carcinoma after previous radiotherapy. The most feared complication after this procedure is a pharyngocutaneous fistula. An extremely rare complication is the development of osteomyelitis of the cervical spine, which is associated with high rates of neurological impairment and epidural empyema, often requiring surgical treatment. This report describes the case of a patient with neck and shoulder pain and progressive motor weakness of the left deltoid and biceps muscle, caused by a pharyngo-cervicospinal fistula with spinal empyema. This condition resulted in destructive osteomyelitis of the cervical spine. A successful reconstruction of the cervical spine and neopharynx was performed using a free vascularized fibula bone and skin graft in a complex area because of previous treatments. It appears that no similar case has been described previously.

[Radiofrequency Ablation for Pulmonary Metastasis of Ovarian Cancer Caused Iatrogenic Pneumothorax, Leading to Empyema].

A female patient in her 40s who underwent surgery for recurrent right lung metastasis from resected ovarian cancer was referred to our department because of the right pneumothorax due to radiofrequency ablation for multiple lung metastases. Methicillin-resistant Staphylococcus epidermidis( MRSE) was detected from the tip of the drainage catheter indicated persistent pulmonary fistula with right empyema, and surgical treatment was performed. A white coat of the whole lung surface and air leakage were observed at radiofrequency ablation (RFA) treated lesion and partial resection of the right lung, debridement, and irrigation were performed. A pathological examination revealed residual viable ovarian cancer cells and pleural fistula.

Bilateral decompressive craniotomy complicated by postoperative mycoplasma hominis epidural empyema and meningitis: A case report.

RATIONALE: Postoperative intracranial mycoplasma hominis infection was a rare complication. Timely diagnosis was difficult due to its growth characteristics and nonspecific clinical symptoms. PATIENT CONCERNS: A 52-year-old man underwent bilateral decompressive craniotomy for severe traumatic brain injury. On the seventeenth day after surgery, the patient developed an unexplained high fever. Empirical anti-infective therapy was ineffective, and the fever persisted. In addition, viscous pus oozed from the head incision. Empiric therapy was still ineffective, the fever persisted, and the culture result was negative. The lumbar puncture pressure was 150 mmH2O and the cerebrospinal fluid white blood cell count was 3600 × 106/L, suggesting an intracranial infection. DIAGNOSES: Culture growth morphologically consistent with mycoplasma species was obtained from multiple specimens (scalp incision fluid and cerebrospinal fluid) and the identification of mycoplasma hominis was confirmed by 16S rDNA sequencing. INTERVENTION: Targeted anti-infective therapy (Minocycline), change of fresh wound dressing, and continued lumbar cerebrospinal fluid drainage. OUTCOME: At the 3-month follow-up, the patient was still in the rehabilitation department of the local hospital for treatment, but there were no symptoms of intracranial infection. LESSONS: Neurosurgeons should carefully examine postoperative incisions and be aware of the possibility of mycoplasma infection during clinical management.

Intrapleural tissue plasminogen activator and deoxyribonuclease administered concurrently and once daily for complex parapneumonic pleural effusion and empyema.

BACKGROUND: Pleural infection is life-threatening and increasingly prevalent. In addition to usual care, twice-daily, separate administration of tissue plasminogen activator and deoxyribonuclease (tPA-DNase) reduces radiological pleural opacity with lower surgical referral rates. AIMS: This retrospective cohort study examines the use of once-daily, concurrent administration of tPA-DNase for complex parapneumonic pleural effusion and empyema. METHODS: Patients with pleural infection who received intrapleural tPA-DNase between October 2014 and July 2020 at Logan Hospital, where it is given concurrently and once-daily as salvage therapy, were retrospectively identified. Radiographic opacification, inflammatory markers, clinical response and complications were examined. RESULTS: Thirty-one patients were identified. Mean age was 48.8 years (standard deviation [SD], 17.2). Median tPA-DNase administration was 3 (interquartile range [IQR], 2-3). Chest x-ray pleural opacity decreased significantly (P = 0.047) from a median of 39.6% (IQR, 28.8-65.7%) to 9.7% (IQR, 2.5-23.2%), a median relative reduction of 75.5% (IQR, 47.7-93.9%). White cell count and C-reactive protein improved significantly (P = 0.002 and P = 0.032, respectively) from a median of 16.3 × 109 /L (IQR, 11.8-20.6 × 109 /L) to 9.9 × 109 /L (IQR, 8.0-12.3 × 109 /L) and 311.0 mg/L (IQR, 218.8-374.0 mg/L) to 69.0 mg/L (IQR, 36.0-118.0 mg/L), respectively. No patients experienced significant bleeding or died. Five patients (16.1%) were referred for surgery. CONCLUSION: This is pilot evidence that a practical regimen of concurrent, once-daily intrapleural tPA-DNase improved pleural opacification and inflammatory markers without bleeding or mortality. The surgical referral rate was higher than in studies assessing twice-daily administration, though the validity of this outcome as a measure of treatment success is limited, and further studies are needed to assess the optimal dose and frequency of intrapleural therapy and indications for surgical referral.

[Postoperative Chylothorax Following Gastric Tube Cancer Surgery Cured after Pneumonia and Empyema-A Case Report].

A 74-year-old man was under follow-up after esophageal cancer surgery and CRT for hypopharyngeal cancer. Follow-up endoscopy revealed an ulcerative lesion in the lower gastric tube, and biopsy showed group 5(tub1). Endoscopic resection was difficult, and surgery was decided. Gastric tube resection and subcutaneous jejunum reconstruction were performed. Postoperatively, chylothorax was observed. Enteral nutrition was discontinued, and the patient was managed with TPN, and continuous subcutaneous octreotide and continuous intravenous etyrefrine were started. Even after conservative treatment was started, the pleural effusion of about 2,000 mL/day was observed from the right thoracic drain. On postoperative day 14, lymphangiography was performed with lipiodol from the left inguinal lymph node. The pleural fluid was temporarily decreased to less than 500 mL/day, but it began to drain again at a rate of 1,000 mL/day. On postoperative day 30, the patient developed fever and elevated inflammatory findings due to pneumonia and empyema, and drain drainage gradually decreased. The drain was removed on postoperative day 41. The patient was discharged home on postoperative day 72.

Hyperammonemia Due to Empyema.

A 91-year-old woman was brought to our hospital with altered consciousness. Blood tests showed an increased ammonia level of 468 µg/dL and a normal liver function. Chest computed tomography showed massive right pleural effusion with loculation. We immediately performed chest drainage using two drainage tubes. The pleural effusate pH was 8.5. We diagnosed her with right empyema leading to hyperammonemia and initiated ampicillin/sulbactam therapy. However, she developed progressive renal failure and died on the third day. Empyema caused by urease-producing bacteria can lead to hyperammonemia. This is the first report of hyperammonemia due to empyema in the English literature.

No role of antibiotics in patients with chest trauma requiring inter-costal drain: a pilot randomized controlled trial.

PURPOSE: To study the role of prolonged prophylactic antibiotic therapy (PAT) in the prevention of Inter-costal drain (ICD) related infectious complications in patients with Blunt Trauma Chest (BTC). METHODS: Patients of age 15 years and above with BTC requiring ICD were included. Patients with penetrating chest injuries, associated injuries/illnesses requiring antibiotic administration, need for mechanical ventilation, known pulmonary disease or immuno-compromised status and need for open thoracotomy were excluded. 120 patients were randomized equally to two groups; no prolonged PAT group (Group A) and prolonged PAT group (group B). Both group patients received one shot of injectable antibiotic prior to ICD insertion. Primary outcome measure was comparison of ICD related infectious complications (pneumonia, empyema and SSI) and secondary outcome measures included the duration of ICD, Length of Hospital stay (LOS) and in-hospital mortality in both the groups. RESULTS: Infectious complications (pneumonia, empyema and SSI) were seen in only one patient in antibiotic group, and none in no antibiotic group (p value = 0.500). Other complications such as post ICD pain scores, respiratory failure requiring ventilatory support, retained hemothorax or recurrent pneumothorax, did not show any statistical difference between both groups. Also, no significant difference was seen in both the groups in terms of mean duration of ICD (p value = 0.600) and LOS (p value = 0.259).m CONCLUSION: Overall prevalence of ICD related infectious complications are low in BTC patients. Definitive role of prolonged prophylactic antibiotics in reducing infectious complications and other associated co morbidities in BTC patients with ICDs could not be established. TRIAL REGISTRY DETAILS: Clinical Trial Registry, India (Trial registered at ctri.nic.in/clinical trials/login.php, number REF/2019/021704 dated 18/10/2019).

Empyema Versus Lung Abscess: A Case Report.

Lung abscesses and empyemas are 2 forms of pulmonary infection that can present with similar clinical features. However, empyemas are associated with higher morbidity and mortality, necessitating the need to distinguish one from the other. Plain radiographs can sometimes provide clues to help differentiate the 2 pathologies but more often than not, a computed tomography scan is required to confirm the diagnosis. Correct diagnosis is essential, as the goal standard therapeutic intervention for empyemas may be contraindicated in patients with lung abscesses. Empyemas require percutaneous or surgical drainage in combination with antibiotics, while lung abscesses are generally treated with antibiotics alone as drainage can be associated with various complications. We present a case of a 65-year-old man with parapneumonic empyema diagnosed with characteristic findings on chest computed tomography and treated with surgical drainage and antibiotics. We hope to improve patient outcomes by highlighting the classical radiographic findings that help distinguish empyema and abscess.

An in Depth Look Into Intracranial Abscesses and Empyemas: a Ten-year Experience in a Single Institute.

Background: As the incidence of intracranial infections increase due to diagnostic procedures improvement, more real-life data is needed to reach a more solid informed management approach. Objective: This study aims to describe and analyse clinical features of intracranial abscesses patients treated at a tertiary hospital in North Jordan during a 10-year period. Methods: We retrospectively identified 37 patients treated at King Abdullah University Hospital (KAUH) from 2011 to 2020 in Irbid, North Jordan. Treatment consisted of either aspiration, open craniotomy excision (OCE) or conservative therapy. Extracted variables included demographic data such (age, gender), clinical presentation, lab findings, radiological findings as well as management plan. Retrieved data was compared between the patients who underwent a single operation and those who underwent reoperation after the initial procedure. Results: Thirty-seven patients with 55 intracerebral abscesses were identified, 29 of whom had intraparenchymal brain abscesses, 4 patients had epidural empyema, and 4 had subdural empyema. The mean age was 28.8 (± 20.7) years, with a male predominance (78.4%). Sixteen patients underwent open craniotomy excision (OCE), 14 patients were treated by aspiration and 7 patients were treated conservatively. When comparing the single operation and the reoperation groups, there was no statistically significant difference across variables. Conclusion: Our study presents valuable insight from a tertiary hospital in north Jordan on intracranial abscesses and empyemas. Our findings confirm that good recovery can be established after aspiration or OCE in the majority of patients. Similar results were obtained when comparing the SOP and the ROP groups.

An Unusual Case of Postpartum Empyema.

We present the case of a 32-year-old woman with a left empyema and T12 osteomyelitis resulting from group B Streptococcus infection occurring 3 weeks after instrumental delivery of a healthy boy. Empyema is a rare complication of instrumental delivery, and this patient highlights the maternal risk resulting from group B Streptococcus bacteremia.

Risk factors for posttraumatic empyema in diaphragmatic injuries.

BACKGROUND: Penetrating diaphragmatic injuries are associated with a high incidence of posttraumatic empyema. We analyzed the contribution of trauma severity, specific organ injury, contamination severity, and surgical management to the risk of posttraumatic empyema in patients who underwent surgical repair of diaphragmatic injuries at a level 1 trauma center. METHODS: This is a retrospective review of the patients who survived more than 48 h. Univariate OR calculations were performed to identify potential risk factors. Multiple logistic regression was used to calculate adjusted ORs and identify independent risk factors. RESULTS: We included 192 patients treated from 2011 to 2020. There were 169 (88.0) males. The mean interquartile range, (IQR) of age, was 27 (22-35) years. Gunshot injuries occurred in 155 subjects (80.7%). Mean (IQR) NISS and ATI were 29 (18-44) and 17 (10-27), respectively. Thoracic AIS was > 3 in 38 patients (19.8%). Hollow viscus was injured in 105 cases (54.7%): stomach in 65 (33.9%), colon in 52 (27.1%), small bowel in 42 (21.9%), and duodenum in 10 (5.2%). Visible contamination was found in 76 patients (39.6%). Potential thoracic contamination was managed with a chest tube in 128 cases (66.7%), with transdiaphragmatic pleural lavage in 42 (21.9%), and with video-assisted thoracoscopy surgery or thoracotomy in 22 (11.5%). Empyema occurred in 11 patients (5.7%). Multiple logistic regression identified thoracic AIS > 3 (OR 6.4, 95% CI 1.77-23. 43), and visible contamination (OR 5.13, 95% IC 1.26-20.90) as independent risk factors. The individual organ injured, or the method used to manage the thoracic contamination did not affect the risk of posttraumatic empyema. CONCLUSION: The severity of the thoracic injury and the presence of visible abdominal contamination were identified as independent risk factors for empyema after penetrating diaphragmatic trauma.

Minimally Invasive Surgical Treatment of Hepatic Hydrothorax Complicated by Empyema: A Case Report.

Hepatic hydrothorax complicated by empyema is difficult to manage. A 53-year-old man with liver cirrhosis was admitted for refractory right pleural effusion. He had a pleural catheter inserted 2 months prior. Pleural fluid appeared as exudate, and bacteria were identified in the pleural fluid culture. After confirming full ipsilateral lung expansion, minimally invasive surgery was performed. A diaphragmatic defect found by creating a pneumoperitoneum was closed, followed by talc pleurodesis. Postoperatively, overnight positive-pressure ventilation and 5-day peritoneal drainage were performed; chest tube drainage dramatically reduced over this time. At the 10-month follow-up, no recurrence of pleural effusion or signs of infection were observed.

Continued Vaccine Breakthrough Cases of Serotype 3 Complicated Pneumonia in Vaccinated Children, Portugal (2016-2019).

We previously reported that despite the use of pneumococcal conjugate vaccines (PCVs), vaccine serotypes remained important causes of pneumonia with pleural effusion and empyema (pediatric complicated pneumococcal pneumonia [PCPP]). We cultured and performed PCR on 174 pleural fluid samples recovered from pediatric patients in Portugal from 2016 to 2019 to identify and serotype Streptococcus pneumoniae. Most PCPP cases (n = 87/98) were identified by PCR only. Serotypes 3 (67%), 14, and 8 (5% each) were the most frequent. Vaccine breakthrough cases were seen among age-appropriately, 13-valent, PCV vaccinated children (median: 3 years, range: 17 months to 7 years), mostly with serotype 3 (n = 27) but also with serotypes 14 and 19A (n = 2 each). One breakthrough was seen with serotype 14 in an age-appropriately, 10-valent, PCV-vaccinated child and another with serotype 3 in a child to whom the 23-valent polysaccharide vaccine was administered. While the relative risk of serotype 1 PCPP decreased almost 10-fold from the period of 2010 to 2015 to the period of 2016 to 2019 (relative risk [RR] = 0.106), that of serotype 3 PCPP almost doubled (RR = 1.835). Our data highlight the importance of molecular diagnostics in identifying PCPP and document the continued importance of serotype 3 PCPP, even when PCV13 use with almost universal coverage could be expected to reduce exposure to this serotype. IMPORTANCE The use of conjugate vaccines against Streptococcus pneumoniae in children has led to substantial reductions in pneumococcal invasive disease. However, the reductions seen in each of the 13 serotypes currently included in the highest-valency vaccine approved for use in children (PCV13), were not the same. It is becoming clear that most vaccine breakthroughs worldwide involve serotype 3 and are frequently associated with complicated pneumonia cases, often with empyema or pleural effusion. Here, we show that despite almost universal PCV13 use, which would be expected to reduce vaccine serotype circulation and further reinforce vaccine direct protection, pneumococci and serotype 3 remain the major causes of pediatric complicated pneumonia. Molecular methods are essential to identify and serotype pneumococci in these cases, which frequently reflect vaccine breakthroughs. A broader use of molecular diagnostics will be essential to determine the role of this important serotype in the context of PCV13 use in different geographic regions.

Spinal infection with intraspinal abscess or empyema and acute myelopathy: comparative analysis of diagnostics, therapy, complications and outcome in primary care.

INTRODUCTION: This study on pyogenic spinal infections with intraspinal epidural involvement (PSI +) compared the outcome of patients with spinal cord injury (SCI) to those without (noSCI) taking diagnostic algorithm, therapy, and complications into account. METHODS: Patients were enrolled in an ambispective study (2012-2017). Diagnostic and therapeutic algorithms, complications, and neurological outcome were analyzed descriptively. Survival was analyzed applying Kaplan-Meier method and Cox regression. RESULTS: In total, 134 patients with a median (IQR) age of 72 (61-79) years were analyzed. Baseline characteristics were similar between the SCI (n = 55) and noSCI (n = 79). A higher percentage of endocarditis (9% vs. 0%; p = 0.03) was detected in the noSCI group. The majority (81%) received combinatorial therapy including spinal surgery and antibiotic treatment. The surgery complication rate was 16%. At discharge, improvement in neurologic function was present in 27% of the SCI patients. Length of stay, duration of ventilation and the burden of disease-associated complications were significantly higher in the SCI group (e.g., urinary tract infection, pressure ulcers). Lethality risk factors were age (HR 1.09, 95% CI 1.02-1.16, p = 0.014), and empyema/abscess extension (≥ 3 infected spinal segments, HR 4.72, 95% CI 1.57-14.20, p = 0.006), dominating over additional effects of Charlson comorbidity index, SCI, and type of treatment. The overall lethality rate was 11%. CONCLUSION: PSI + are associated with higher in-hospital mortality, particularly when multiple spinal segments are involved. However, survival is similar with (SCI) or without myelopathy (noSCI). If SCI develops, the rate of disease complications is higher and early specialized SCI care might be substantial to reduce complication rates.