Diagnostic Algorithm for the Diagnosis of Pediatric Parasitic Gastroenteritis.

BACKGROUND: Current practices for ordering stool studies in patients with abdominal and gastrointestinal symptoms are not standardized. We hypothesized that an algorithm involving first-line use of a Cryptosporidium/Giardia combination antigen test and stricter use of ova and parasite (O&P) examinations would be clinically and cost effective. METHODS: In this study, stool O&P test results for pediatric patients in Dallas, Texas, were reviewed. All results obtained between 2009 and 2012 were included. Patient charts were reviewed to determine test results, symptoms, treatment, travel, and past medical history. Using these data, a retrospective modeling study was done to evaluate the utility of a diagnostic algorithm that limits O&P testing to those patients who are immunocompromised or have travelled outside the United States. RESULTS: Over the 3-year period of this study, we found that the prevalence of gastrointestinal parasitic disease in children was 1.9%. Analysis of the diagnostic algorithm for the judicious use of stool O&P showed that as much as 65% of testing may be unnecessary and could be eliminated. CONCLUSIONS: Our findings show that the prevalence of pediatric gastrointestinal parasitic disease in Texas may be lower than expected. In addition, these data show that a diagnostic algorithm limiting O&P testing may be both clinically and cost effective in low-prevalence settings. However, such an algorithm would miss a significant number of infections due to Dientamoeba fragilis and Blastocystis hominis.

Detection of intracellular parasites by use of the CellaVision DM96 analyzer during routine screening of peripheral blood smears.

Conventional microscopy is the gold standard for malaria diagnosis. The CellaVision DM96 is a digital hematology analyzer that utilizes neural networks to locate, digitize, and preclassify leukocytes and characterize red blood cell morphology. This study compared the detection rates of Plasmodium and Babesia species on peripheral blood smears utilizing the CellaVision DM96 with the rates for a routine red blood cell morphology scan. A total of 281 slides were analyzed, consisting of 130 slides positive for Plasmodium or Babesia species and 151 negative controls. Slides were blinded, randomized, and analyzed by CellaVision and microscopy for red cell morphology scans. The technologists were blinded to prior identification results. The parasite detection rate was 73% (95/130) for CellaVision and 81% (105/130) for microscopy for positive samples. The interobserver agreement between CellaVision and microscopy was fair, as Cohen's kappa coefficient equaled 0.36. Pathologist review of CellaVision images identified an additional 15 slides with parasites, bringing the total number of detectable positive slides to 110 of 130 (85%). Plasmodium ovale had the lowest rate of detection at 56% (5 of 9); Plasmodium malariae and Babesia spp. had the highest rate of detection at 100% (3/3 and 6/6, respectively). The detection rate by CellaVision was 100% (23/23) when the parasitemia was ≥2.5%. The detection rate for <0.1% parasitemia was 63% (15/24). Technologists appropriately classified all negative specimens. The percentage of positive specimens detectable by CellaVision (73%) approaches results for microscopy on routine scan of peripheral blood smears for red blood cell morphology.

Evaluation of the nanosphere verigene gram-positive blood culture assay with the VersaTREK blood culture system and assessment of possible impact on selected patients.

The Verigene Gram-positive blood culture (BC-GP) assay (Nanosphere, Northbrook, IL) is a molecular method for the rapid identification of Gram-positive organisms and resistance markers directly from blood culture bottles. A total of 148 VersaTREK REDOX 1 40-ml aerobic bottles demonstrating Gram-positive bacteria were tested. Results were compared with those from conventional biochemical and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) identifications. We obtained isolates of methicillin-resistant Staphylococcus aureus (MRSA) (24), methicillin-susceptible Staphylococcus aureus (MSSA) (14), methicillin-resistant Staphylococcus epidermidis (MRSE) (17), methicillin-susceptible Staphylococcus epidermidis (MSSE) (9), other coagulase-negative staphylococci (19), Streptococcus salivarius (5), Streptococcus parasanguinis (2), Streptococcus sanguinis (1), Streptococcus cristatus (1), the Streptococcus bovis group (5), Streptococcus agalactiae (9), the Streptococcus anginosus group (1), Streptococcus pneumoniae (6), vancomycin-resistant Enterococcus faecium (VRE FCM) (16), vancomycin-susceptible Enterococcus faecalis (3), Aerococcus viridans (2), Bacillus (6), Corynebacterium (8), Lactobacillus (2), Micrococcus (2), Neisseria mucosa (1), Escherichia coli (3), Candida tropicalis (1), Propionibacterium (1), and Rothia (1). Overall agreement with the culture results was 95%. A total of 137 of 138 (99%) monomicrobial cultures were concordant. We tested 9 polymicrobial samples and found 33% agreement. A chart review of 31 patients with MRSA, MSSA, or VRE demonstrated that the Nanosphere BC-GP assay might have led to more appropriate antibiotic selection for these patients an average of 42 h earlier. Additionally, contact isolation could have been initiated an average of 37 h earlier for patients with MRSA or VRE. The BC-GP assay may have a positive impact on patient care, health care costs, and antibiotic stewardship.

Pseudo-outbreak of vancomycin-resistant-enterococcus (VRE) Colonization in a neonatal intensive care unit using spectra VRE surveillance medium.

From November 2011 through March 2012, we surveyed 272 babies in our neonatal intensive care unit for rectal colonization with vancomycin-resistant enterococci (VRE). Using Spectra VRE medium (Remel Diagnostics, Lenexa, KS), we identified one neonate colonized with vancomycin-resistant Enterococcus faecium. In addition, 55 (13%) of the surveillance cultures yielded false-positive results with vancomycin-susceptible Enterococcus faecalis. During the same time period, 580 rectal swabs were collected from adult patients resulting in 20 (3%) false-positive cultures. The difference in false-positive rates between cultures from babies and adults was statistically significant (P < 0.001), prompting an investigation of factors that might influence the elevated false-positive rate in the neonates including patient demographics, nutrition, and topical ointments applied at the time of testing. Older neonates, with a median age of 6 weeks, were more likely to have false-positive cultures than younger neonates with a median age of 3 weeks (P < 0.001). The younger neonates receiving Similac Expert Care products were less likely to have false-positive surveillance cultures than those receiving other formulas (P < 0.001). Application of topical products was not associated with false-positive cultures. The false-positive E. faecalis strains were typed by Diversilab Rep-PCR (bioMérieux, Marcy l'Etoile, France) and found to represent eight different groups of isolates. The utility of the Spectra VRE media appeared to be significantly impacted by the age of the patients screened.

Prompt control of an outbreak caused by extended-spectrum ß-lactamase-producing Klebsiella pneumoniae in a neonatal intensive care unit.

OBJECTIVES: To assess the effectiveness of a set of multidisciplinary interventions aimed at limiting patient-to-patient transmission of extended-spectrum ß-lactamase-producing Klebsiella pneumoniae (ESBL-KP) during a neonatal intensive care unit (NICU) outbreak, and to identify risk factors associated with ESBL-KP colonization and disease in this setting. STUDY DESIGN: A 61-infant cohort present in the NICU during an outbreak of ESBL-KP from April 26, 2011, to May 16, 2011, was studied. Clinical characteristics were compared in infected/colonized infants and unaffected infants. A multidisciplinary team formulated an outbreak control plan that included (1) staff reeducation on recommended infection prevention measures; (2) auditing of hand hygiene and environmental services practices; (3) contact precautions; (4) cohorting of infants and staff; (5) alleviation of overcrowding; and (6) frequent NICU-wide screening cultures. Neither closure of the NICU nor culturing of health care personnel was instituted. RESULTS: Eleven infants in this level III NICU were infected/colonized with ESBL-KP. The index case was an 18-day-old infant born at 25 weeks' gestation who developed septicemia from ESBL-KP. Two other infants in the same room developed sepsis from ESBL-KP within 48 hours; both expired. Implementation of various infection prevention strategies resulted in prompt control of the outbreak within 3 weeks. The ESBL-KP isolates presented a single clone that was distinct from ESBL-KP identified previously in other units. Being housed in the same room as the index infant was the only risk factor identified by logistic regression analysis (P = .002). CONCLUSION: This outbreak of ESBL-KP affected 11 infants and was associated with 2 deaths. Prompt control with eradication of the infecting strain from the NICU was achieved with multidisciplinary interventions based on standard infection prevention practices.

First reported Rhodotorula mucilaginosa brain abscess: Found as coinfection in woman with common variable immune deficiency.

Rhodotorula is a rare pathogen seen in the immunocompromised host; while cases of Rhodotorula meningitis have been reported, there are no published cases of Rhodotorula brain abscess. We describe the diagnosis and management of a woman with common variable immune deficiency presenting with concomitant Rhodotorula and Nocardia brain abscesses.

Cutaneous fusariosis developing in a post-irradiation site.

Cutaneous fusariosis is an opportunistic mycosis in immunocompromised patients. We present a novel variation of an immunocompromised patient who developed fusariosis in a previously irradiated site. Irradiation led to atrophy, contraction, fibrosis, barrier disruption, and an altered dermal environment in which the infection developed. Significantly, this is the first case report of fusariosis in a previously irradiated site of an immunocompromised patient. Treatment included debridement and voriconazole.

Impact of blood cultures drawn by phlebotomy on contamination rates and health care costs in a hospital emergency department.

We conducted a prospective comparison of blood culture contamination rates associated with dedicated phlebotomists and nonphlebotomy staff in the emergency department (ED) at Parkland Memorial Hospital in Dallas, TX. In addition, hospital charges and lengths of stay were determined for patients with negative, false-positive, and true-positive blood culture results. A total of 5,432 blood culture collections from two ED areas, the western wing of the ED (ED west) and the nonwestern wing of the ED (ED nonwest), were evaluated over a 13-month period. Phlebotomists drew 2,012 (55%) of the blood cultures in ED west while nonphlebotomy staff drew 1,650 (45%) in ED west and 1,770 (100%) in ED nonwest. The contamination rates of blood cultures collected by phlebotomists were significantly lower than those collected by nonphlebotomists in ED west (62/2,012 [3.1%] versus 122/1,650 [7.4%]; P < 0.001). Similar results were observed when rates between phlebotomists in ED west and nonphlebotomy staff in ED nonwest were compared (62/2,012 [3.1%] versus 100/1,770 [5.6%]; P < 0.001). Comparison of median patient charges between negative and false-positive episodes ($18,752 versus $27,472) showed $8,720 in additional charges per contamination event while the median length of stay increased marginally from 4 to 5 days. By utilizing phlebotomists to collect blood cultures in the ED, contamination rates were lowered to recommended levels, with projected reductions in patient charges of approximately $4.1 million per year.

Fascioliasis in pregnancy.

BACKGROUND: Fascioliasis is a common zoonotic infection worldwide, although cases in the United States are uncommon, sporadic, and predominantly found in the immigrant population. The small number of cases identified in the United States may reflect the unfamiliarity of physicians with this infection. CASE: A 28-year-old Hispanic woman who frequently visited northern Central Mexico presented at 36 weeks of gestation with nausea, vomiting, and right upper quadrant pain. She was diagnosed with cholelithiasis. Postpartum endoscopic retrograde cholangiopancreatography and sphincterotomy were performed, with discovery of the trematode Fasciola hepatica. The patient received triclabendazole, which led to clinical improvement. CONCLUSION: Fascioliasis often mimics another common problem in pregnancy, cholelithiasis; clinicians need to be aware of this disease in high-risk populations.

Acinetobacter infections and outcomes at an academic medical center: a disease of long-term care.

Background. Our study aims to describe the epidemiology, microbial resistance patterns, and clinical outcomes of Acinetobacter infections at an academic university hospital. This retrospective study analyzed all inpatient clinical isolates of Acinetobacter collected at an academic medical center over 4 years. The data were obtained from an Academic tertiary referral center between January 2008 and December 2011. All consecutive inpatients during the study period who had a clinical culture positive for Acinetobacter were included in the study. Patients without medical records available for review or less than 18 years of age were excluded. Methods. Records were reviewed to determine source of isolation, risk factors for acquisition, drug resistance patterns, and clinical outcomes. Repetitive sequence-based polymerase chain reaction of selected banked isolates was used to determine patterns of clonal spread in and among institutions during periods of higher infection rates. Results. Four hundred eighty-seven clinical isolates of Acinetobacter were found in 212 patients (in 252 admissions). Patients with Acinetobacter infections were frequently admitted from healthcare facilities (HCFs) (59%). One hundred eighty-three of 248 (76%) initial isolates tested were resistant to meropenem. One hundred ninety-eight of 249 (79.5%) initial isolates were multidrug resistant (MDR). Factors associated with mortality included bacteremia (odds ratio [OR] = 1.93, P = .024), concomitant steroid use (OR = 2.87, P < .001), admission from a HCF (OR = 6.34, P = .004), and chronic obstructive pulmonary disease (OR = 3.17, P < .001). Conclusions. Acinetobacter isolates at our institution are frequently MDR and are more common among those who reside in HCFs. Our findings underline the need for new strategies to prevent and treat this pathogen, including stewardship efforts in long-term care settings.

Case report: ophthalmomyiasis externa in Dallas County, Texas.

Ophthalmomyiasis externa is an uncommon condition in North America. If not recognized and managed accordingly, it can be complicated by the potentially fatal condition ophthalmomyiasis interna. Ophthalmomyiasis externa is mainly caused by the sheep bot fly Oestrus ovis; thus, it is more common in farming communities. We report a case of ophthalmomyiasis externa in a young woman from Dallas County, Texas, who had no known history of contact with farm animals.

Splenic abscess with Vibrio cholerae masking pancreatic cancer.

A 77-year-old man presented to our hospital with a clinical scenario suspicious for endocarditis with septic emboli to the lungs and splenic abscess. Vibrio cholerae was isolated from purulent material aspirated from the abscess. Medical therapy and percutaneous drainage of the abscess were unsuccessful. The patient underwent splenectomy and distal pancreatectomy revealing a pancreatic tail carcinoma involving the spleen and colon. The patient later expired secondary to metastatic disease. This case represents the first isolation of V. cholerae from a splenic abscess but also illustrates that although newer imaging technologies have made the diagnosis of splenic abscess easier, the true etiology of the abscess may remain elusive.

Clinical features of West Nile virus epidemic in Dallas, Texas, 2012.

In 2012, Texas has reported the highest number of West Nile virus (WNV) cases in the United States to the Centers for Disease Control and Prevention. In this report, we conducted a retrospective chart review of 57 patients with WNV disease and analyzed the clinical features of these patients. Our results revealed that 25 (44%) patients were diagnosed with West Nile fever and 32 (56%) with West Nile neuroinvasive disease (WNND). The median age for patients with WNND was 54.5 years, and those with encephalitis were more likely to be >60 years old. Pre-existing conditions such as hypertension and diabetes were more frequent in patients with WNND. Testing both serum and cerebrospinal fluid (CSF) for antibodies diagnosed more cases of WNND than just testing serum or CSF alone. The increasing number of WNV cases during this epidemic highlights the need to increase efforts to control mosquito populations and educate the general public.

Mycobacterium leprae and Mycobacterium haemophilum co-infection in an iatrogenically immunosuppressed patient.

We present the case of a native Texan who was diagnosed with tuberculoid leprosy and later developed a cutaneous infection with M. haemophilum following iatrogenic immunosuppression. To our knowledge, there are no such reports of M. haemophilum and M. leprae infection occurring simultaneously in the same host.

Comparison of endoscopically-guided swab vs aspirate culture techniques in post-endoscopic sinus surgery patients: blinded, prospective analysis.

BACKGROUND: Culture-directed antibiotic therapy remains imperative in the management paradigm of chronic rhinosinusitis (CRS). The objective of this study was to conduct a prospective, blinded comparison of endoscopically-guided swab and aspirate cultures from the same sinonasal site in patients presenting with acute infectious exacerbations post-sinus surgery. METHODS: Forty-nine CRS patients were prospectively enrolled in a tertiary care rhinology clinic. At the conclusion of the study, all cultures were unblinded to determine mean culture yield, most common pathogens, potential contaminants, and therapeutic correlation. RESULTS: The mean patient age was 49 years and 40.8% were males. All patients had evidence of symptomatic exacerbation with purulence on endoscopy at the time of presentation. There was a mean of 1.367 pathogens assayed per aspirate culture vs a mean of 1.102 per swab culture (p = 0.0032). The prevalence of Pseudomonas aeruginosa was 42% for aspirate vs 30% for swab cultures, respectively. The prevalence of Staphylococcus aureus was 49% for suction cultures vs 45% for swab cultures. There were 9 and 11 likely contaminants using aspirate and swab cultures, respectively. Therapeutic correlation was strong in 67%, moderate in 18%, and weak in 14% of patients. CONCLUSION: This prospective analysis demonstrated higher culture yield, particularly with Pseudomonas, with aspirate vs swab cultures in postoperative patients. There is a strong clinical correlation between the 2 methods, and both aspirate and swab techniques serve as acceptable alternatives for endoscopic-guided cultures in patients with post-functional endoscopic sinus surgery infectious exacerbations.

Controlling outbreak of vancomycin-resistant Enterococcus faecium among infants caused by an endemic strain in adult inpatients.

BACKGROUND: Vancomycin-resistant Enterococcus faecium (VREfm) is commonly associated with hospital outbreaks and has been found to be associated with increased morbidity, mortality, length of stay, and health care costs. METHODS: We sought to investigate and control an outbreak of VREfm in the neonatal intensive care unit (NICU) of a public academic hospital with a level III NICU. The index case was an infant in the NICU incidentally identified with urinary colonization with VREfm. Aggressive control measures were initiated promptly. Investigation included active surveillance cultures in infants, parents of colonized infants, and birth mothers of newborn admitted to NICU; molecular strain typing of available isolates of VREfm including adult inpatients; and medical record review. RESULTS: After identification of index case, 13 additional infants were identified with VREfm colonization. Age at culture was 6 to 87 days; birth weight was 1,070 to 2,834 g. VREfm isolated from majority of infants (12/14 [85.7%]), the birth mother of a pair of colonized twins, and a pulse oximeter device used in adult inpatients belonged to a single strain. Outbreak control measures were successful in the NICU. The outbreak-causing strain was found to be endemic among adult inpatients. Adult patients with the outbreak-causing strain of VREfm were more likely to have received previous therapy with meropenem (Mann-Whitney 2-tailed P value = .038). VRE colonization was identified in 0.3% (1/310) of birth mothers with newborn admitted to NICU. CONCLUSION: An endemic strain of VREfm among adult inpatients was responsible for a subsequently controlled outbreak in the NICU.

Interpretation of positive molecular tests of common viruses in the cerebrospinal fluid.

Many central nervous system infections are historically difficult to diagnose. Polymerase chain reaction (PCR) has revolutionized the diagnosis of these infections because of their high sensitivity despite the lack of data on clinical usefulness. We conducted a retrospective study that included patients with positive cerebrospinal fluid (CSF) PCR for herpes simplex virus, varicella-zoster virus, JC virus, cytomegalovirus (CMV), and Epstein-Barr virus (EBV) between January 2009 and December 2011. The positive results were grouped into definite, likely, and possible true positives and likely false-positive categories based on pre-specified definitions specific to each virus. Of 1663 CSF viral PCR tests, 88 were positive (5%). The combined positive predictive value (PPV) was 58%. The PPVs were least for CMV and EBV at 29 and 37%, respectively. A positive CSF viral PCR result has to be interpreted with caution due to several false-positive results.

Subcutaneous phaeohyphomycosis caused by Cladophialophora bantiana.

Primary subcutaneous phaeohyphomycosis can rarely be caused by Cladophialophora bantiana, and we present the histologic and culture findings of such a case. A 32-year-old African American woman with systemic lupus erythematosus presented with a 2-year history of multiple, recurrent, tender, and ulcerated skin nodules with purulent drainage on her upper back. Histologic sections of the excision demonstrated features of phaeohyphomycosis. Culture findings were characteristic of C bantiana. Of interest, at age 10 she had sustained traumatic implantation of wood splinters into this area during a tornado, yet clinical symptoms of a subcutaneous infection did not manifest until she developed lupus erythematosus at age 27. Our case highlights the role of trauma and immunosuppression in the pathogenesis of subcutaneous phaeohyphomycosis.

Reflex human papillomavirus DNA testing on residual liquid-based (TPPT) cervical samples: focus on age-stratified clinical performance.

BACKGROUND: Liquid-based ThinPrep technology has made reflex human papillomavirus (HPV) DNA testing possible. In the current study, the clinical performance of reflex HPV testing as an adjunct to routine ThinPrep testing (TPPT) and the impact of age on various test parameters in a predominantly high-risk, minority population were evaluated retrospectively. METHODS: Reflex HPV testing was performed in 2114 women with atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesion (LSIL) cytology, using probes for low-risk (LR) and high-risk (HR) HPV types. Six hundred thirty women underwent subsequent biopsies with which HPV testing results were correlated. RESULTS: Approximately 86% of the patients were Hispanic and African-American and 12% were white. Of the younger women (ages 14-29 years), 81% were positive for HR types versus 50% in the older women (ages 30-77 years) (P < 0.0001). In women with ASCUS, 47% were found to be positive for HR types versus 78% of women with LSIL. The percentage of histologic high-grade lesions was 24% in younger patients versus 17% in older patients. Overall, 91% of high-grade lesions were positive for HPV DNA (HR-positive = 89% and LR-positive = 2%), and 9% were negative for both types. The sensitivities and specificities in "younger" versus "older" women were 92% (95% confidence interval [95% CI], 89-95%) and 22%% (95% CI, 17-26%), respectively, versus 84% (95% CI, 77-90%) and 59% (95% CI, 53-65%), respectively. CONCLUSIONS: The results of the current study demonstrate that reflex HPV testing performed in a routine clinical practice helps to identify the majority of women with high-grade disease. However, testing may be more beneficial in older women (age > or = 30 years) with ASCUS. Strategy using out-of-vial reflex testing is more cost-effective and sensitive than referring all women for colposcopies.