Sternoclavicular septic arthritis caused by Staphylococcus aureus: excellent results from medical treatment and limited surgery

Background: Aggressive surgery such as en bloc joint resection is favored for treating uncommon sternoclavicular (SC) septic arthritis, based on expert opinion and small case series. We analyzed the clinical characteristics and treatment outcomes of patients with Staphylococcus aureus SC septic arthritis treated medically or with limited surgery. Methods: All adult patients with this septic arthritis at the Asan Medical Center between September 2009 and December 2016 were reviewed. Limited surgery was defined as simple incision, drainage, and debridement of the infected joint. Results: Of 22 patients enrolled, 11 received medical treatment only, and 11 underwent limited surgery, and none underwent aggressive surgery. Most patients (73%) had underlying predisposing conditions such as infection at a distant site, diabetes and liver cirrhosis, and none had intravenous drug abuse or HIV infection. Complications such as chest wall and/or neck abscess, clavicular and/or sternal osteomyelitis were identified in 18 patients (82%). Patients with chest wall and/or neck abscesses tended more often to undergo limited surgery than patients without such abscesses (73% vs. 27%, p = .09). The median duration of intravenous antibiotics was 35 days (IQR, 25-46 days). Treatment was successful in all cases. In a median 53-week follow-up (IQR, 8-171 weeks), there was no relapse of arthritis or joint deterioration. Conclusions: Medical treatment alone or with limited surgery could be successful therapeutic strategies for complicated S. aureus SC septic arthritis in selected patients.

Neurocysticercosis: Clinical Characteristics and Changes from 26 Years of Experience in an University Hospital in Korea

The prevalence of human taeniasis has decreased in Korea. The stool egg positive proportion decreased from 1.9% in 1971 to 0% in 2004 in nationwide surveys. The neurocysticercosis (NCC) is also presumed to decrease. However, detailed information regarding the recent status of NCC in Korea is lacking. We retrospectively reviewed NCC cases from 1990 to 2016 at Asan Medical Center, a 2700-bed tertiary referral hospital in Korea. We identified patients based on clinical symptoms, brain imaging, pathology and serological assay. The cases were classified as parenchymal, extraparenchymal, and mixed NCC. Eighty-one patients were included in the analysis. The mean age was 54.5 years, and 79.0% were male. The number of NCC cases was highest from 1995 to 1999, and continuously decreased thereafter. Forty (49.4%) patients had parenchymal NCC, while 25 (30.9%) patients had extraparenchymal NCC, and 16 (19.8%) patients had mixed NCC. The seizure and headache were most common symptom of parenchymal NCC and extraparenchymal NCC respectively. Hydrocephalus was more common in extraparenchymal NCC, and patients with extraparenchymal NCC were more likely to require a ventriculoperitoneal shunt. Cases of NCC are decreasing accordingly with human taeniasis and lesion location was the most important determinant of clinical presentation and outcome of NCC in Korea.

Clinical characteristics and treatment outcomes of Enterococcus durans bacteremia: a 20-year experience in a tertiary care hospital

While the clinical characteristics and treatment outcomes of Enterococcus faecalis and E. faecium bacteremia are well known, those of E. durans bacteremia are still largely unclear. We retrospectively identified 80 adult E. durans bacteremia cases treated at our 2700-bed tertiary care hospital between January 1997 and December 2016. We compared the clinical characteristics and treatment outcomes of the adult patients with E. durans bacteremia (case group) with those of E. faecalis and E. faecium bacteremia cases (two control groups). The case and control groups were matched for sex, age, and date of onset of bacteremia. E. durans was responsible for 1.2% of all enterococcal bacteremia cases at our hospital. Of 80 cases, 39 (48.8%) had biliary tract infection and 18 (22.5%) had urinary tract infection. Community-onset bacteremia was more frequent in the case group than in the control groups (56.2% vs. 35.0% vs. 21.2%, p < 0.01). Infective endocarditis tended to be more common in the E. durans group (7.5% vs. 1.2% vs. 1.2%, p = 0.05). The majority of E. durans isolates were susceptible to penicillin (66/76, 86.8%), ampicillin (67/76, 88.2%), and vancomycin (75/76, 98.7%). The case group had significantly lower all-cause mortality (20.0% vs. 31.2% vs. 42.5%, p < 0.01) and bacteremia-related mortality (2.5% vs. 16.2% vs. 18.8%, p < 0.01) than the control groups. E. durans bacteremia mainly originates from the biliary or urinary tract and is associated with a lower risk of mortality.

Invasive fungal infection in liver transplant recipients in a prophylactic era: A multicenter retrospective cohort study in Korea

The epidemiology of invasive fungal infections (IFIs) after liver transplantation (LT) is continuing to evolve in the current era of antifungal prophylactic therapy. This multicenter retrospective cohort study aimed to evaluate the epidemiology, risk factors, and outcomes of IFIs among LT recipients in the current era.We analyzed a total of 482 LT recipients aged 18 years and older who were admitted to 3 tertiary hospitals in Korea between January 2009 and February 2012.Twenty-four episodes of IFIs occurred in 23 patients (4.77%; 23/482). Of these episodes, 20 were proven cases and 4 were probable cases according to EORTC/MSG criteria. Among these cases, IFI developed within 30 days of transplantation in 47.8% of recipients, from 31 to 180 days in 34.8% of recipients, and from 181 to 365 days in 17.4% of recipients. The most common isolates were Candida species (n = 12, 52.2%; Candida albicans, 6 cases; Candida tropicalis, 1 case; Candida glabrata, 1 case; Candida parapsilosis, 1 case; and unspecified Candida species, 1 case) and Aspergillus species (n = 7, 30.4%). The mortality in patients with IFIs was significantly higher than that in patients without IFIs (47.83% [11/23] vs 7.18% [33/459], P < .001). The incidence of late-onset IFIs is increasing in the antifungal prophylactic era, and fluconazole-resistant non-albicans Candida species have not yet emerged in Korea.

Diagnostic usefulness of molecular detection of Coxiella burnetii from blood of patients with suspected acute Q fever

Diagnosis of Q fever is difficult due to the lack of distinct clinical features that distinguish it from other febrile diseases. Serologic testing is the gold standard method for diagnosing Q fever, but antibody formation may not be detectable for 2 to 3 weeks from symptom onset, limiting early diagnosis. We thus evaluated the diagnostic utility of polymerase chain reaction (PCR) to detect Coxellia burnetii DNA in serum from patients with suspected acute Q fever.All adult patients with suspected acute Q fever were prospectively enrolled at a tertiary-care hospital from January 2016 through July 2018. Acute Q fever was diagnosed using clinical and laboratory criteria: fever with at least one other symptoms (myalgia, headache, pneumonia, or hepatitis) and single phase II immunoglobulin G (IgG) antibody titers ≥1:200 or immunoglobulin M (IgM) antibody titer ≥1:50 (probable), or a fourfold increase or seroconversion in phase II IgG antibody titers as measured by indirect immunofluorescence assays between paired samples (confirmed). We performed PCR targeting the transposase gene insertion element IS1111a of C. burnetii.Of the 35 patients with suspected acute Q fever, 16 (46%) were diagnosed with acute Q fever including 8 probable and 8 confirmed cases; the remaining 19 (54%) were diagnosed with other febrile diseases. The proportion of males diagnosed with Q fever was higher than those diagnosed with other febrile diseases (88% vs 44%, P = .03), but there were no other significant differences in clinical characteristics between the 2 groups. The Q fever PCR sensitivity was 81% (95% confidence interval [CI], 54-96), specificity was 90% (95% CI, 67-99), positive predictive value was 87% (95% CI, 63-96), and negative predictive value was 85% (95% CI, 67-94).Q fever PCR testing using blood from patients with suspected acute Q fever seems to be a rapid and useful test for early diagnosis of Q fever.

Can endoscopists differentiate cytomegalovirus esophagitis from herpes simplex virus esophagitis based on gross endoscopic findings?

Differential diagnosis between herpes simplex virus (HSV) esophagitis and cytomegalovirus (CMV) esophagitis is challenging because there are many similarities and overlaps between their endoscopic features. The aims of this study were to investigate the implications of the endoscopic findings for the diagnosis of HSV and CMV esophagitis, and to develop a predictive model for differentiating CMV esophagitis from HSV esophagitis.Patients who underwent endoscopic examination and had pathologically-confirmed HSV or CMV esophagitis were eligible. Clinical characteristics and endoscopic features were retrospectively reviewed and categorized. A predictive model was developed based on parameters identified by logistic regression analysis.During the 8-year study period, HSV and CMV esophagitis were diagnosed in 85 and 63 patients, respectively. The endoscopic features of esophagitis were categorized and scored as follows: category 1 (-3 points): discrete ulcers or ulcers with vesicles, bullae, or pseudomembranes, category 2 (-2 points): coalescent or geographic ulcers, category 3 (1 points): ulcers with an uneven base, friability, or with a circumferential distribution, category 4 (2 points): punched-out, serpiginous, or healing ulcers with yellowish exudates. And previous history of transplantation (2 point) was included in the model as a discriminating clinical feature. The optimal cutoff point of the prediction model was 0 (area under receiver operating characteristic curve: 0.967), with positive scores favoring CMV esophagitis. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 96.8%, 89.4%, 92.6%, 87.3%, and 97.5%, respectively.The predictive model based on endoscopic and clinical findings appears to be accurate and useful in differentiating CMV esophagitis from HSV esophagitis.

Correlation of fungal cultures from non-sterile sites and Galactomannan assay with the diagnosis of aspergillosis and mucormycosis based on sterile culture results and histopathologic findings

BACKGROUND

Data on whether positive non-sterile fungal culture has the same clinical value as a positive galactomannan (GM) result are limited.

METHODS

Patients with biopsy-proven invasive aspergillosis or mucormycosis (over an 8-year period) in whom the results of GM and fungal culture of sputum and/or sinus aspirates were available were enrolled. Biopsy-proven cases were defined if fungal culture from a sterile biopsy specimen gave a positive result and/or hyphae were demonstrated by immunohistochemical staining for aspergillosis and mucormycosis.

RESULTS

A total of 71 patients comprising 30 biopsy-proven cases of aspergillosis including 13 cases with positive sterile cultures and 41 biopsy-proven cases of mucormycosis including eight cases with positive sterile cultures were enrolled. Of 30 patients with aspergillosis, 15 (50%) revealed Aspergillus spp. growth from non-sterile site and none exhibited the agents of mucormycosis growth from non-sterile site. However, of 41 patients with mucormycosis, eight (20%) revealed the agents of mucormycosis growth from non-sterile site and three (7%) exhibited Aspergillus spp. growth from non-sterile site. In terms of GM assays, 23 (77%) of 30 patients with aspergillosis revealed positive GM results, and 17 (41%) of 41 patients with mucormycosis revealed positive GM assays. So, positive fungal culture from non-sterile site (88% [23/26]) were better correlated with the diagnosis than positive GM assay (57% [23/40]) (p value = .01).

CONCLUSIONS

Positive fungal cultures from non-sterile sites better correlate with the diagnosis of aspergillosis and mucormycosis based on sterile culture results and histopathological findings than positive GM results.

Diagnostic Usefulness of Varicella-Zoster Virus Real-Time Polymerase Chain Reaction Analysis of DNA in Saliva and Plasma Specimens From Patients With Herpes Zoster

Background

We evaluated the diagnostic usefulness of polymerase chain reaction (PCR) analysis for detecting varicella-zoster virus (VZV) infection and reactivation of VZV, using DNA extracted from saliva and plasma specimens obtained from subjects with suspected herpes zoster and from healthy volunteers during stressful and nonstressful conditions.

Methods

There were 52 patients with a diagnosis of herpes zoster (group 1), 30 with a diagnosis of zoster-mimicking disease (group 2), and 27 healthy volunteers (group 3). Saliva and plasma samples were evaluated for VZV DNA by real-time PCR analysis.

Results

Among patients with suspected herpes zoster (ie, patients in groups 1 and 2), the sensitivity of PCR analysis of salivary DNA for detecting VZV (88%; 95% confidence interval [CI], 74%-95%) was significantly higher than that of PCR analysis of plasma DNA (28%; 95% CI, 16%-44%; P < .001), whereas the specificity of PCR analysis of salivary DNA (100%; 95% CI, 88%-100%) was similar to that of PCR analysis of plasma DNA (100%; 95% CI, 78%-100%; P > .99). VZV DNA was not detected in saliva and plasma samples from group 3 (0%; 95% CI, 0%-14%).

Conclusions

Real-time PCR analysis of salivary DNA is more sensitive than that of plasma DNA for detecting VZV among patients with suspected herpes zoster. We found no subclinical reactivation of VZV in group 3 following exposure to common stressful conditions.

Selection of an appropriate empiric antibiotic regimen in hematogenous vertebral osteomyelitis

Background

Empiric antibiotic therapy for suspected hematogenous vertebral osteomyelitis (HVO) should be initiated immediately in seriously ill patients and may be required in those with negative microbiological results. The aim of this study was to inform the appropriate selection of empiric antibiotic regimens for the treatment of suspected HVO by analyzing antimicrobial susceptibility of isolated bacteria from microbiologically proven HVO.

Method

We conducted a retrospective chart review of adult patients with microbiologically proven HVO in five tertiary-care hospitals over a 7-year period. The appropriateness of empiric antibiotic regimens was assessed based on the antibiotic susceptibility profiles of isolated bacteria.

Results

In total, 358 cases of microbiologically proven HVO were identified. The main causative pathogens identified were methicillin-susceptible Staphylococcus aureus (33.5%), followed by methicillin-resistant S. aureus (MRSA) (24.9%), Enterobacteriaceae (19.3%), and Streptococcus species (11.7%). Extended spectrum β-lactamase (ESBL)-producing Enterobacteriaceae and anaerobes accounted for only 1.7% and 1.4%, respectively, of the causative pathogens. Overall, 73.5% of isolated pathogens were susceptible to levofloxacin plus rifampicin, 71.2% to levofloxacin plus clindamycin, and 64.5% to amoxicillin-clavulanate plus ciprofloxacin. The susceptibility to these oral combinations was lower in cases of healthcare-associated HVO (52.6%, 49.6%, and 37.6%, respectively) than in cases of community-acquired HVO (85.8%, 84.0%, and 80.4%, respectively). Vancomycin combined with ciprofloxacin, ceftriaxone, ceftazidime, or cefepime was similarly appropriate (susceptibility rates of 93.0%, 94.1%, 95.8%, and 95.8%, respectively).

Conclusions

Based on our susceptibility data, vancomycin combined with a broad-spectrum cephalosporin or fluoroquinolone may be appropriate for empiric treatment of HVO. Fluoroquinolone-based oral combinations may be not appropriate due to frequent resistance to these agents, especially in cases of healthcare-associated HVO.

Clinical Characteristics and Radiologic Features of Immunocompromised Patients With Pauci-Bacillary Pulmonary Tuberculosis Receiving Delayed Diagnosis and Treatment

Background

Pauci-bacillary pulmonary tuberculosis (TB) can be delayed to diagnose and start anti-TB therapy, especially in immunocompromised patients. We therefore evaluated the clinical and radiologic features of these delayed cases.

Methods

Immunocompromised adult patients with pauci-bacillary pulmonary TB were retrospectively enrolled in a tertiary hospital in an intermediate–TB burden country over a 5-year period. We defined “missed TB” or “not-missed TB” patients as those who started anti-TB therapy after or before positive mycobacterial culture results, respectively.

Results

Of 258 patients, 134 (52%) were classified in the missed TB group, and 124 (48%) in the not-missed TB group. Positive results of molecular tests including MTB polymerase chain reaction and/or Xpert TB/RIF were only obtained in the not-missed TB group (54/106, 54%). The median diagnostic delay in the missed TB group was longer than in the other group (30 vs 6 days; P < .001). In the missed TB group, the most common working diagnoses were pneumonia (46, 34%) and lung metastasis of malignancy (40, 30%). Typical radiologic findings for TB, such as upper lobe predominance and centrilobular nodules with tree-in-bud appearance, were less common in the missed TB group than in the other group. Old age (odds ratio [OR], 1.03), solid organ transplant (OR, 3.46), solid tumor (OR, 3.83), and hematologic malignancy (OR, 4.04) were independently associated with missed TB.

Conclusions

Care is needed to differentiate pauci-bacillary TB, especially in immunocompromised patients with the mentioned risk factors, even without the usual radiologic features of TB. Additional rapid diagnostic tests to rule out pauci-bacillary TB are urgently needed.

Clinical and microbiological factors associated with early patient mortality from methicillin-resistant Staphylococcus aureus bacteremia

BACKGROUND/AIMS

Methicillin-resistant Staphylococcus aureus bacteremia (MRSAB) is a major bloodstream infection with a high mortality rate. Identification of factors associated with early mortality in MRSAB patients would be useful for predicting prognosis and developing new therapeutic options.

METHODS

A prospective cohort of MRSAB patients was examined between August 2008 and June 2011. Early and late mortality was defined as death within 2 and 28 days of blood culture, respectively. The clinical and microbiological characteristics in the early and late mortality and survival groups were compared. Risk factors associated with severe sepsis or septic shock were also investigated.

RESULTS

A total of 385 adult MRSAB patients whose S. aureus isolates were available were enrolled; of these patients, 25 patients (6.5%) and 50 (13%) died early and late, respectively. Compared with both the late-mortality group and the survival group, severe sepsis or septic shock was a statistically significant independent risk factor associated with early mortality. Rapidly or ultimately fatal McCabe and Jackson classification (adjusted odds ratio [aOR], 1.94; 95% confidence interval [CI], 1.25 to 3.02) and pneumonia (aOR, 2.04; 95% CI, 1.03 to 4.02) were independently associated with severe sepsis or septic shock. A vancomycin minimum inhibitory concentration (MIC) ≥ 1.5 μg/mL was associated with a reduced incidence of severe sepsis or septic shock (aOR, 0.53; 95% CI, 0.34 to 0.84).

CONCLUSION

Severity of illness seems to be the most important risk factor associated with early mortality in MRSAB. Although vancomycin MIC was not independently associated with early mortality, reduced vancomycin susceptibility appears to be linked to reduced disease severity.

Improvement of blood culture contamination rate, blood volume, and true positive rate after introducing a dedicated phlebotomy team

The introduction of dedicated phlebotomy teams certified for blood collection has been reported to be highly cost-effective by reducing contamination rates. However, data on their effects on blood volume and true positive rate are limited. Therefore, we investigated the effect of replacing interns with a phlebotomy team on blood culture results. We performed a 24-month retrospective, quasi-experimental study before and after the introduction of a phlebotomy team dedicated to collecting blood cultures in a 2700-bed tertiary-care hospital. The microbiology laboratory database was used to identify adult patients with positive blood culture results. During the study period, there were no changes in blood collection method, blood culture tubes, and the application of antiseptic measures. Blood volume was measured by the BACTEC™ FX system based on red blood cell metabolism. A total of 162,207 blood cultures from 23,563 patients were analyzed, comprising 78,673 blood cultures during the intern period and 83,534 during the phlebotomy team period. Blood volume increased from a mean of 2.1 ml in the intern period to a mean of 5.6 ml in the phlebotomy team period (p < 0.001). Introduction of the phlebotomy team also reduced contamination rate (0.27% vs. 0.45%, p < 0.001) and led to a higher true positive rate (5.87% vs. 5.01%, p < 0.05). The increased true positive rate associated with the phlebotomy team involved both gram-positive and gram-negative bacteria. The introduction of a dedicated phlebotomy team can increase blood volumes, reduce blood culture contamination rate, and increase true positive rate.

Factors associated with sequelae after treatment of hematogenous pyogenic vertebral osteomyelitis

OBJECTIVES

Functional disability may persist after completing treatment for hematogenous pyogenic vertebral osteomyelitis (HPVO). The objective of this study was to identify factors associated with residual sequelae after treatment of HPVO.

METHODS

We conducted a retrospective study of patients diagnosed with HPVO at 5 tertiary-care hospitals between January 2005 and December 2012. Sequelae were defined as an inability to walk without assistance, bladder/bowel incontinence, and/or unresolved pain that required analgesic therapy at 12 months after completing the HPVO treatment.

RESULTS

Of the 279 patients with microbiologically proven HPVO, 79 (28.3%) had sequelae at 12 months posttherapy. Independent risk factors for sequelae were neurologic deficit (adjusted odds ratio [aOR], 3.38), recurrence within 12 months (aOR, 2.45), age ≥ 65 years (aOR, 2.05), C-reactive protein level ≥ 10 mg/dL (aOR, 2.01), and epidural/paravertebral abscess (aOR, 2.00). Among 58 patients with neurologic deficit, sequelae rates differed according to the surgical strategy, as follows: 28.6% (early surgery [<48 h]), 55.0% (delayed surgery [≥48 h]), and 66.7% (no surgery) (P = 0.03). Among the 170 patients with abscess, early drainage (<72 h) was an independent protective factor for sequelae (aOR, 0.35). The 12-month recurrence rates differed according to the total duration of antibiotic treatment, as follows: 20.5% (4-6 weeks), 18.4% (6-8 weeks), and 5.2% (≥8 weeks) (P < 0.001).

CONCLUSIONS

A substantial proportion of patients with HPVO experienced sequelae after completing treatment. Early surgery for neurologic deficit, early drainage of abscess, and antibiotic therapy of appropriate duration to reduce recurrence may prevent development of sequelae in patients with HPVO.

Clinical characteristics and outcomes of patients with chronic disseminated candidiasis who need adjuvant corticosteroid therapy

We performed a retrospective study involving 21 patients with chronic disseminate candidiasis (CDC) and 38 patients with candidemia. Neutropenia of >2 weeks' duration was more common in those with CDC (71%) than in those with candidemia (26%, P < .001), and the azole-resistant rate in patients with CDC (5%) was lower than that in those with candidemia (29%, P = .03). Of the 21 patients with CDC, five (24%) needed adjuvant corticosteroid therapy due to persistent debilitating fever (median, 19 days). Rapid defervescence (median, 5 days) occurred after adjuvant corticosteroid therapy. However, there were no significant differences in 90-day mortality between CDC patients with and without corticosteroid therapy. Further prospective data are needed to define the role of steroids in this setting.

414. Diagnostic Usefulness of Differential Time to Positivity (DTP) in Neutropenic Cancer Patients With Suspected Catheter-Related Candidemia (CRC)

Background

Methods

Results

Conclusion

Disclosures

400. The Frequency and Clinical Characteristics of Positive Galactomannan Assay Results in Patients With Mucormycosis

Background

Discrepancies between histomorphologic finding and indirect test results such as galactomannan (GM) assay make diagnosis of invasive fungal infection difficult. We investigated the frequency and clinical characterisitics of positive GM assay results in patients with mucormycosis.

Methods

Patients who met the modified criteria for proven or probable mucormycosis and had serum and/or bronchoalveolar lavage (BAL) fluid GM assay result were enrolled at a tertiary hospital from July 2009 to October 2017. Proven mucormycosis was defined as histologic evidence of tissue invasion of hyphae with positive mucormycosis immunohistochemistry (IHC) test result and the recovery of agents of mucormycosis (Rhizopus spp., Cunninghamella spp., Apophysomyces spp., Saksenaea spp., Absidia spp., Mucor spp.) by culture from sterile specimens. Probable mucormycosis was defined as histologic evidence of tissue invasion of hyphae with positive mucormycosis IHC test result with or without recovery of agents of mucormycosis by culture from nonsterile specimens.

Results

Among 50 patients of proven or probable mucormycosis, 20 (40%) patients were positive for serum and/or BAL fluid GM assay results; 13 of 20 (65.0%) were positive in serum, nine of 12 (75.0%) were positive in BAL fluid, and two of 12 (16.7%) were positive in both. There were more patients with gastrointestinal infections (4 of 20 [20%] vs. 0 of 30 [0%], P = 0.021) and diagnosed as histomorphologically aspergillosis (6 of 20 [30%] vs. 1 of 30 [3%], P = 0.012) in GM positive group than GM negative group.

Conclusion

These results suggest that positive GM assay results are not uncommon in mucormycosis. GM assay results from the patients with mucormycosis appear to be related with gastrointestinal infections and histomorphologic diagnosis of aspergillosis. Further studies are needed on the mechanism of positive GM results in patients with mucormycosis and possible coinfection with other fungi such as Aspergillus species in these patients.

Disclosures

S. H. Kim, the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI): Investigator, Grant recipient

419. Diagnostic Performance of Immunohistochemistry Test to Differentiate Aspergillosis from Mucormycosis With Formalin-Fixed Tissue Specimens

Background

Distinguishing aspergillosis from mucormycosis is clinically important as different antifungal agents are required. However, the sensitivity of fungal culture is suboptimal and histomorphologic diagnosis is not always accurate due to morphologic similarities. We investigated the diagnostic performance of immunohistochemistry (IHC) test for diagnosis of aspergillosis and mucormycosis.

Methods

Patients who met the criteria for mycologically proven aspergillosis or mucormycosis and in whom formalin-fixed, paraffin-embedded tissues were available were enrolled at a tertiary hospital from January 1992 to October 2017. Mycologically proven invasive fungal infections were defined as there were the histologic evidence of tissue invasion of hyphae and the recovery of Aspergillus species or agents of mucormycosis (Rhizopus spp., Cunninghamella spp., Apophysomycesspp., Saksenaea spp., Absidia spp., Mucor spp.) by culture from sterile specimens. Anti-Aspergillus mouse monoclonal antibody (1:50; clone WF-AF-1; LSBio, WA, USA) and anti-Rhizopus arrhizus mouse monoclonal antibody (1:100; clone WSSA-RA-1; LSBio, WA, USA) were used for IHC test, and we evaluated the diagnostic performance of IHC test using sensitivity and specificity.

Results

A total of 32 invasive fungal infection including 12 proven mucormycosis and 20 proven aspergillosis were analyzed. The fungal species from sterile sites and diagnostic performance of IHC test for these 30 patients were shown in Table 1.

Conclusion

The IHC test seems to be useful in compensating the limitations of histomorphologic diagnosis in distinguishing between aspergillosis and mucormycosis.

Keywords. Aspergillosis; Mucormycosis; Histomorphology; Immunohistochemistry

Disclosures

S. H. Kim, the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI): Investigator, Grant recipient.

The Results of In Situ Prosthetic Graft Replacement for Infected Aortic Disease

BACKGROUND

Infected aortic disease is a serious clinical condition associated with significant morbidity and mortality. This study reviewed the outcomes of in situ aortic replacement with a prosthetic graft for infected aortic disease, including primary infected abdominal aortic aneurysms (PIAAA), infected aortic prosthetic grafts (IAPG), and infected aortic stent grafts (IASG).

METHODS

Twenty-eight consecutive patients who underwent in situ aortic replacement with a prosthetic graft for PIAAA, IAPG, and IASG at a single center from January 2001 to December 2015 were retrospectively analyzed. Demographics, clinical characteristics, medical management, surgical procedure, and clinical outcomes were included.

RESULTS

Nineteen patients with a PIAAA, three with an IAPG following open repair of abdominal aortic aneurysm (AAA), and six with an IASG following endovascular aortic repair underwent in situ prosthetic graft replacement with infected tissue and graft removal. In-hospital mortality was 7.1% (2/28). One died of bleeding on postoperative day 12, and the other died of hepatic failure on postoperative day 32. Of six patients with an IASG, two had major complications that were related to barb injury at the proximal aorta. The reinfection rate was 14.3% (4 of 28) during a mean follow-up of 35.7 months (1-142 months). All new grafts of three patients with IAPG were reinfected. The other patient became reinfected after surgery for PIAAA with iatrogenic small bowel perforation that was not detected during surgery.

CONCLUSIONS

In situ graft replacement of PIAAA and IASG is feasible with acceptable outcomes, but the outcome for IAPG is questionable.

The First Living-Donor Lobar Lung Transplantation in Korea: a Case Report

Lung transplantation is the only treatment for end-stage lung disease, but the problem of donor shortage is unresolved issue. Herein, we report the first case of living-donor lobar lung transplantation (LDLLT) in Korea. A 19-year-old woman patient with idiopathic pulmonary artery hypertension received her father's right lower lobe and her mother's left lower lobe after pneumonectomy of both lungs in 2017. The patient has recovered well and is enjoying normal social activity. We think that LDLLT could be an alternative approach to deceased donor lung transplantation to overcome the shortage of lung donors.

Molecular detection of Coxiella burnetii in heart valve tissue from patients with culture-negative infective endocarditis

Coxiella burnetii is a common cause of blood culture-negative infective endocarditis (IE). Molecular detection of C burnetii DNA in clinical specimens is a promising method of diagnosing Q fever endocarditis. Here, we examined the diagnostic utility of Q fever polymerase chain reaction (PCR) of formalin-fixed heart valve tissue from patients with blood culture-negative IE who underwent heart valve surgery. Clinical and laboratory data of patients with blood culture-negative IE who underwent heart valve surgery during a 6-year period and for whom biopsy tissues were available were reviewed retrospectively. Blood culture-positive IE patients who underwent heart valve surgery within the last 3 years were used as controls. Heart valve samples were cultured and also subjected to histological examination and PCR for Q fever, brucellosis, and bartonellosis. Data from 20 patients with blood culture-negative IE and 20 with blood culture-positive IE were analyzed. Eight cases of blood culture-negative IE were PCR-positive for C burnetii (40%; 95% confidence interval, 19-64). No specimen was PCR-positive for brucellosis or bartonellosis. Histologically, 4 of 8 specimens with a positive Q fever PCR result were characterized by clusters of multinucleated giant cells without a fibrin ring. None of 20 patients with blood culture-negative IE received anti-Coxiella antibiotic therapy due to lack of clinical suspicion. Six-month mortality was higher in the Q fever PCR-positive group than in the Q fever PCR-negative group [38% (3/8) vs 0% (0/12), P = .049). Of the 20 patients with blood culture-positive IE, none yielded a positive Q fever PCR result for valve tissue. Approximately 40% of patients with culture-negative IE who received heart valve surgery were PCR-positive for Q fever; patients without clinical suspicion suffered high mortality. These data suggest that Q fever IE in patients with culture-negative IE is often missed in routine clinical practice.

"Turn-On" Fluorescent and Colorimetric Detection of Zn2+ Ions by Rhodamine-Cinnamaldehyde Derivative

We report the design and synthesis of a novel chemosensor (Rh6G-Cin) rhodamine-based indicator for selective detection of Zn2+ ion. Rh6G-Cin displayed high selectivity towards Zn2+ from various metal ions, including Ca2+, Ag+, Cd2+, Co2+, Cu2+, Al3+, Zn2+, Cr3+, Ba2+, Fe2+, Fe3+, Gd3+, Hg2+, Mg2+, Mn2+, Nd3+, Pb2+, Sr2+ and Ni2+, and the resultant complex is [Rh6G-Cin-Zn2+]. The obvious change from colorless to pink upon the addition of Zn2+ could make it a suitable "naked eye" indicator for Zn2+. More significantly, the sensor displayed a remarkable colorless to yellowish green fluorescence switch in the presence of Zn2+ ions. The ring-opening mechanism of the rhodamine spirolactam was induced by Zn2+ binding, and the 3:1 stoichiometric structure between Rh6G-Cin and Zn2+ was adequately supported by the Job's plot evaluation, optical titration and 1H NMR results.

Combined IFN-γ and TNF-α release assay for differentiating active tuberculosis from latent tuberculosis infection

OBJECTIVES

The IFN-γ-release assay (IGRA) cannot differentiate active tuberculosis (TB) from latent TB infection (LTBI). We hypothesized that the TNF-α-release assay (TARA) combined with IGRA might discriminate active TB from not active TB without LTBI.

METHODS

Adult patients with suspected TB, and with unrelated diseases such as herpes zoster as controls, were enrolled in an intermediate TB-burden country. Patients with confirmed or probable TB were regarded as active TB, and patients with not active TB were further classified as those having not active TB with and without LTBI based on IGRA results. The IGRA and TARA by using ELISPOT assays were performed on peripheral mononuclear cells.

RESULTS

Thirty six patients with active TB and 53 patients including 18 not active TB with LTBI and 35 not active TB without LTBI were finally included. The sensitivity and specificity of the IGRA for those patients found to have active TB were 94% (CI, 80-99) and 66% (CI 52-78), respectively. Combining the IGRA and the TARA substantially increased the specificity for active TB (93%, CI, 82-98; P = 0.001) compared with the IGRA only, without compromising sensitivity (89%, CI, 73-96; P = 0.67).

CONCLUSIONS

Combining the IGRA and TARA appears to be useful for diagnosing active TB.

Korean clinical practice guidelines for preventing the transmission of infections in hemodialysis facilities

Patients receiving hemodialysis are vulnerable to infectious diseases due to their impaired immunity and high risk of exposure to pathogens. To protect patients, staff, and visitors from potential infections, each hemodialysis unit should establish and follow standard infection control and prevention measures. Therefore, clinical practice guidelines were developed by a working group of nephrologists and infection control specialists to provide evidence-based guidance for dialysis physicians and nurses, with the aim of preventing infection transmission and controlling infection sources in hemodialysis facilities. The areas of infection control covered by these guidelines include standard precautions, isolation strategies, vascular access, water treatment, cleaning/disinfecting/sterilizing, and vaccination. This special report summarizes the key recommendations from the Korean clinical practice guidelines for preventing the transmission of infections in hemodialysis facilities.

Pneumocystis pneumonia versus rituximab-induced interstitial lung disease in lymphoma patients receiving rituximab-containing chemotherapy

It is difficult to differentiate Pneumocystis pneumonia (PCP) from rituximab-induced interstitial lung disease (RILD) in lymphoma patients with diffuse pulmonary infiltrates who are receiving rituximab-containing chemotherapy. Using a clinical scoring system, we aim to differentiate PCP from RILD who are receiving rituximab-containing chemotherapy. We reviewed the medical records of lymphoma patients who had received rituximab-containing chemotherapy between 2012 and 2015 in a tertiary hospital. Among 613 lymphoma patients receiving rituximab-containing chemotherapy, 97 (16%) had diffuse pulmonary infiltrates. Of these, 16 (16%) with an alternative diagnosis and 22 (23%) with an indeterminate diagnosis were excluded. Finally, 21 (22%) patients were classified as having PCP and the remaining 38 (39%) as having RILD. Fever, short duration of symptoms (≤5 days), systemic inflammatory response syndrome (SIRS), and severe extent of disease on CT scan (>75%) were more common in patients with PCP than in those with RILD. Clinical scores were determined using the following system: SIRS = score 1, symptom duration ≤5 days = score 1, extent of disease on CT >75% = score 4. A score of ≥2 differentiated PCP from RILD with 91% sensitivity (95% CI, 70-99) and 71% specificity (95% CI, 54-84). A clinical scoring system based on presence of SIRS, short duration of symptoms, and severe extent of disease on CT scan appears to be useful in differentiation of PCP from RILD.