Do bed bugs transmit human viruses, or do humans spread bed bugs and their viruses? A worldwide survey of the bed bug RNA virosphere

BED BUGS: (Hemiptera: Cimicidae) are a globally distributed hematophagous pest that routinely feed on humans. Unlike many blood-sucking arthropods, they have never been linked to pathogen transmission in a natural setting, and despite increasing interest in their role as disease vectors, little is known about the viruses that bed bugs naturally harbor. Here, we present a global-scale survey of the bed bug RNA virosphere. We sequenced the metatranscriptomes of 22 individual bed bugs (Cimex lectularius and Cimex hemipterus) from 8 locations around the world. We detected sequences from two known bed bug viruses (Shuangao bedbug virus 1 and Shuangao bedbug virus 2) which extends their geographical range. We identified three novel bed bug virus sequences from a tenui-like virus (Bunyavirales), a toti-like virus (Ghabrivirales), and a luteo-like virus (Tolivirales). Interestingly, some of the bed bug viruses branch near to insect-transmitted plant-infecting viruses, opening questions regarding the evolution of plant virus infection. When we analyzed the viral sequences by their host's collection location, we found unexpected patterns of geographical diversity that may reflect humans' role in bed bug dispersal. Additionally, we investigated the effect that Wolbachia, the primary bed bug endosymbiont, may have on viral abundance and found that Wolbachia infection neither promotes nor inhibits viral infection. Finally, our results provide no evidence that bed bugs transmit any known human pathogenic viruses.

Decoding Immuno-Competence: A Novel Analysis of Complete Blood Cell Count Data in COVID-19 Outcomes

BACKGROUND

While 'immuno-competence' is a well-known term, it lacks an operational definition. To address this omission, this study explored whether the temporal and structured data of the complete blood cell count (CBC) can rapidly estimate immuno-competence. To this end, one or more ratios that included data on all monocytes, lymphocytes and neutrophils were investigated.

MATERIALS AND METHODS

Longitudinal CBC data collected from 101 COVID-19 patients (291 observations) were analyzed. Dynamics were estimated with several approaches, which included non-structured (the classic CBC format) and structured data. Structured data were assessed as complex ratios that capture multicellular interactions among leukocytes. In comparing survivors with non-survivors, the hypothesis that immuno-competence may exhibit feedback-like (oscillatory or cyclic) responses was tested.

RESULTS

While non-structured data did not distinguish survivors from non-survivors, structured data revealed immunological and statistical differences between outcomes: while survivors exhibited oscillatory data patterns, non-survivors did not. In survivors, many variables (including IL-6, hemoglobin and several complex indicators) showed values above or below the levels observed on day 1 of the hospitalization period, displaying L-shaped data distributions (positive kurtosis). In contrast, non-survivors did not exhibit kurtosis. Three immunologically defined data subsets included only survivors. Because information was based on visual patterns generated in real time, this method can, potentially, provide information rapidly.

DISCUSSION

The hypothesis that immuno-competence expresses feedback-like loops when immunological data are structured was not rejected. This function seemed to be impaired in immuno-suppressed individuals. While this method rapidly informs, it is only a guide that, to be confirmed, requires additional tests. Despite this limitation, the fact that three protective (survival-associated) immunological data subsets were observed since day 1 supports many clinical decisions, including the early and personalized prognosis and identification of targets that immunomodulatory therapies could pursue. Because it extracts more information from the same data, structured data may replace the century-old format of the CBC.

A metatranscriptomic evaluation of viruses in field-collected bed bugs

Cimex lectularius, known as the common bed bug, is a widespread hematophagous human ectoparasite and urban pest that is not known to be a vector of any human infectious disease agents. However, few studies in the era of molecular biology have profiled the microorganisms harbored by field populations of bed bugs. The objective of this study was to examine the viruses present in a large sampling of common bed bugs and related bat bugs (Cimex pipistrelle). RNA sequencing was undertaken on an international sampling of > 500 field-collected bugs, and multiple workflows were used to assemble contigs and query these against reference nucleotide databases to identify viral genomes. Shuangao bed bug virus 2, an uncharacterized rhabdovirus previously discovered in Cimex hemipterus from China, was found in several bed bug pools from the USA and Europe, as well as in C. pipistrelle, suggesting that this virus is common among bed bug populations. In addition, Shuangao bed bug virus 1 was detected in a bed bug pool from China, and sequences matching Enterobacteria phage P7 were found in all bed bug pools, indicating the ubiquitous presence of phage-derived elements in the genome of the bed bug or its enterobacterial symbiont. However, viral diversity was low in bed bugs in our study, as no other viral genomes were detected with significant coverage. These results provide evidence against frequent virus infection in bed bugs. Nonetheless, our investigation had several important limitations, and additional studies should be conducted to better understand the prevalence and composition of viruses in bed bugs. Most notably, our study largely focused on insects from urban areas in industrialized nations, thus likely missing infrequent virus infections and those that could occur in rural or tropical environments or developing nations.

Patient and Provider Demographics and the Management of Genitourinary Tract Infections in the Emergency Department

Introduction

Urinary tract infections (UTIs) and sexually transmitted infections (STIs) can have overlapping signs, symptoms, and findings on urinalysis. Our objective was to determine if patient or provider demographics are associated with differences in the diagnosis and management of UTIs and STIs in the emergency department (ED).

Methods

We analyzed 38,062 ED patient encounters from a single healthcare system between April 18, 2014, and March 7, 2017. All encounters were women ≥18 years of age and not admitted to the hospital. We performed logistic regression using patient and provider demographics, laboratory testing results, ED triage data, and ED diagnoses.

Results

The patient's age, race, and marital status were not associated with having an ED UTI diagnosis with a urine culture ≥10,000 colony forming units (CFUs)/mL (vs. <10,000 CFUs/mL). Patient race and the sex of the ED provider were not associated with differences in empiric antibiotic treatment for gonorrhea and chlamydia during the ED encounter. Patient's race and the sex of the ED provider were also not associated with discordance between empiric antibiotic therapy given in the ED and the results of gonorrhea and chlamydia tests that resulted following the ED encounter.

Conclusion

In our multivariate analyses, we did not observe that the patient's race resulted in significant differences in the diagnosis of UTIs with bacteriuria ≥10,000 CFU/mL or differences in the empiric treatment of gonorrhea and chlamydia infections among those tested for the infection in the ED. The patient's age and marital status, but not the provider's sex, were significantly associated with differences in the management of gonorrhea and chlamydia.

Analysis of Patients With Bed Bugs in the Emergency Department

The objective was to evaluate the clinical characteristics, triage information, diagnostic evaluation, and disposition for emergency department patients with and without bed bug infestation. A retrospective case-control study of patients with and without bed bugs was performed from February 1, 2011, through February 1, 2017. Cases (n = 332) and controls (n = 4,952) were matched by age, sex, and emergency department location. Patient characteristics and clinical information were compared between groups. On univariable and multivariable analysis, patients with bed bugs had higher heart rate, lower systolic blood pressure, higher pain scores, and more frequent tobacco use in the past year. They were also more likely to screen positive in triage for an unsafe home; require an abuse consultation; be diagnosed in the emergency department or inpatient setting with malnutrition, marasmus, and/or cachexia; have more emergency department and hospital visits; and have longer hospital encounter lengths of stay (all p ≤ 0.02). On univariable analysis, patients with bed bugs were also more likely than uninfested controls to be single, be Black, come to the emergency department from home, arrive to the emergency department by ambulance, and not be discharged back to their homes from the hospital.

Descriptive Epidemiology of Women in the Emergency Department With Gonorrhea and Chlamydial Infection in the United States

Demographic characteristics, risk factors, and clinical variables associated with gonorrhea and chlamydial infection in women being treated in emergency departments (EDs) in the United States are incompletely characterized. We used univariable and multivariable regression analyses on 17,411 encounters from women 18 years and older who presented to EDs in northeast Ohio and were tested for gonorrhea or chlamydial infection. There were 1,360 women (7.8%) who had Chlamydia trachomatis infection and 510 (2.9%) who had Neisseria gonorrhoeae infection. Those infected with C. trachomatis or N. gonorrhoeae were younger (23.8 vs. 29.2 years), unmarried (97.7% vs. 90.1%), Black (93.3% vs. 88.0%), infected with Trichomonas vaginalis (39.9% vs. 27.2%), diagnosed with urinary tract infection (15.7% vs. 10.6%), and treated for gonorrhea and chlamydial infection during the ED visit (31.6% vs. 17.4%) (all ps < .001). Women infected with C. trachomatis or N. gonorrhoeae had more urine white blood cells (WBCs) (23.9 vs. 16.4 cells per high-power field [HPF]) and leukocyte esterase (1.2+ vs. 0.8+) on urinalysis. They had more WBCs (18.5 vs. 12.4 cells/HPF) and odds of having T. vaginalis infection (12.8% vs. 8.2%) on vaginal wet preparation (all ps < .001). Women infected with C. trachomatis were more likely to be younger and not Black; they were less likely to be treated for gonorrhea and chlamydial infection in the ED and to have lower levels of urine WBCs, leukocyte esterase, and blood than those infected with N gonorrhoeae (all ps ≤ .05).

Alkaline Urine in the Emergency Department Predicts Nitrofurantoin Resistance

BACKGROUND

The Proteeae group (i.e., Proteus species, Morganella morganii, and Providencia species) frequently causes urinary tract infections (UTIs) and is generally resistant to nitrofurantoin. Proteeae species can produce urease, which can increase urine pH.

OBJECTIVE

Our aim was to determine whether higher urine pH in the emergency department is associated with nitrofurantoin resistance.

METHODS

A single health system database of emergency department patients aged 18 years and older who received urinalysis between April 18, 2014, and March 7, 2017, was examined using χ² test and multivariable regression analysis.

RESULTS

Of 67,271 urine samples analyzed, 13,456 samples grew a single bacterial species. Urine cultures growing the Proteeae group were associated with significantly more alkaline urine than other bacteriuria cultures (odds ratio [OR] 2.20, 95% confidence interval [CI] 2.06-2.36; p < 0.001). The Proteeae species represented 4.4% of urine samples at pH 5-7, 24.4% at pH 8-9, and 40.0% at pH 9. At urine pH 5-7, 80.4% of urine samples were sensitive to nitrofurantoin; however, this percentage decreased to 66.1% for urine pH 8-9 and 54.6% for urine pH 9. Nitrofurantoin had the highest OR (2.10, 95% CI 1.85-2.39) among cefazolin, ciprofloxacin, and trimethoprim/sulfamethoxazole for bacteriuria sensitive to those antibiotics at urine pH 5-7. At urine pH 8-9 and 9, nitrofurantoin had the lowest OR among the antibiotics: 0.48 (95% CI 0.42-0.54) and 0.31 (95% CI 0.24-0.40), respectively (p < 0.001 for both).

CONCLUSIONS

Urine pH of 8 or higher is associated with high rates of nitrofurantoin resistance.

Prediction model for gonorrhea, chlamydia, and trichomoniasis in the emergency department

OBJECTIVE

History and physical examination findings can be unreliable for prediction of genitourinary tract infections and differentiation of urinary tract infections from sexually transmitted infections (STIs). The study objective was to develop a prediction tool to more accurately identify patients with STIs.

METHODS

A retrospective review of 64,490 emergency department (ED) encounters between April 18, 2014, and March 7, 2017, where patients age 18 years or older had urinalysis and urine culture or testing for gonorrhea, chlamydia, or trichomonas, was used to develop a prediction model for men and women with Neisseria gonorrhoeae or Chlamydia trachomatis, or both, and for women with Trichomonas vaginalis. The data set was randomly divided into two-thirds discovery and one-third validation. Groups were assigned through a random number generator. Backward step regression modeling was used to identify the best model for each outcome.

RESULTS

With use of age, race, marital status, and findings from vaginal wet preparation (white blood cells [WBCs], clue cells, and yeast) and urinalysis (squamous epithelial cells, protein, leukocyte esterase, and WBCs), the models had areas under the receiver operating characteristic curve of 0.80 for men with N gonorrhoeae or C trachomatis, or both; 0.75 for women with N gonorrhoeae or C trachomatis, or both; and 0.73 for women with T vaginalis.

CONCLUSIONS

The model estimated likelihood of ED patients having STIs was reasonably accurate with a limited number of demographic and laboratory variables. In the absence of point-of-care STI testing, use of a prediction tool for STIs may improve antimicrobial stewardship.

Wilderness Medical Society Clinical Practice Guidelines for the Prevention and Management of Tick-Borne Illness in the United States

The Wilderness Medical Society convened an expert panel to develop evidence-based guidelines for the prevention and management of tick-borne illness (TBI). Recommendations are graded based on quality of supporting evidence according to criteria put forth by the American College of Chest Physicians. The guidelines include a brief review of the clinical presentation, epidemiology, prevention, and management of TBI in the United States, with a primary focus on interventions that are appropriate for resource-limited settings. Strong recommendations are provided for the use of DEET, picaridin, and permethrin; tick checks; washing and drying clothing at high temperatures; mechanical tick removal within 36 h of attachment; single-dose doxycycline for high-risk Lyme disease exposures versus "watchful waiting;" evacuation from backcountry settings for symptomatic tick exposures; and TBI education programs. Weak recommendations are provided for the use of light-colored clothing; insect repellents other than DEET, picaridin, and permethrin; and showering after exposure to tick habitat. Weak recommendations are also provided against passive methods of tick removal, including the use of systemic and local treatments. There was insufficient evidence to support the use of long-sleeved clothing and the avoidance of tick habitat such as long grasses and leaf litter. Although there was sound evidence supporting Lyme disease vaccination, a grade was not offered as the vaccine is not currently available for use in the United States.

Investigating the association of bed bugs with infectious diseases: A retrospective case-control study

Bed bugs are common urban pests. Unlike many other blood-feeding human ectoparasites, bed bugs are not known to be vectors of human infectious diseases, but clinical and epidemiological studies to directly interrogate this link have been limited. Here, we aimed to determine whether bed bugs were associated with infectious diseases in a set of infested patients presenting to emergency departments (ED) in the greater Cleveland, OH area. We performed a retrospective case-control study involving 332 ED patients with bed bugs and 4,952 control patients, seen from February 1, 2011, through February 1, 2017. Cases and controls were matched by age, sex, and the presenting ED. Additionally, data were adjusted for ≥20 sociodemographic variables, triage data, and comorbidities in multivariable regression analyses. Seventeen laboratory values, ten different ED and inpatient diagnoses, chest radiographs, infectious disease consults, and blood cultures were examined. The odds of bed bug infestation were significantly higher for patients that had positive blood cultures, had blood cultures growing coagulase-negative Staphylococcus, were diagnosed with pneumonia, were diagnosed with cellulitis, received an infectious disease consult, received a chest radiograph, and had higher percentages of eosinophils in the blood (P < .05 for all). Additional investigations are needed to determine whether bed bugs directly contribute to disease by transmitting causative agents, whether bed bug exposure contributes secondarily contributes to infections, or whether these associations are better explained by other environmental and social determinants of health.

Respiratory diseases in patients with bed bugs

INTRODUCTION

Some arthropods such as cockroaches can exacerbate asthma, but it is unknown is this is true of bed bugs.

OBJECTIVES

The objective of this work is to determine if bronchospastic diseases like asthma and chronic obstructive pulmonary disease (COPD) would be higher for ED patients who have bed bug infestation compared with patients who do not have bed bug infestation.

METHODS

A case-control study was performed with 332 adult emergency department (ED) patients with bed bug infestation and 4952 without infestation. Univariable and multivariable regression analysis was performed.

RESULTS AND CONCLUSION

Patients with bed bug infestation were not more likely to have a past history of or an ED diagnosis of asthma or chronic obstructive pulmonary disease (COPD). However, bed bug infested patients were significantly more likely to undergo chest radiography, be admitted to the hospital, and receive albuterol in the ED (P < 0.05). Infested patients receiving albuterol in the ED were more likely to be admitted to the hospital compared with uninfested patients receiving albuterol (P < 0.001). Patients with an ED or inpatient diagnosis of asthma or COPD and bed bugs (compared with those without bed bugs) had significantly more ED visits during the study (P < 0.03). Bed bug infestations may be associated with respiratory pathology, which requires further investigation.

Infrarenal aortic balloon-expandable stent graft deployment using the sheath control technique in a patient with hemorrhagic shock secondary to an aortoenteric fistula

A 40-year-old man presented with hemorrhagic shock owing to an aortoduodenal fistula. Angiography demonstrated vasospasm of the right common femoral artery to 2 mm. Treatment using a balloon-expandable stent graft was chosen given the smaller sheath diameter requirement when compared to self-expandable aortic stent graft. Given the undersized 11 mm delivery balloon for the patient's aorta, a sheath control technique was utilized. The stent graft was partially expanded within the sheath and the delivery balloon was exchanged for a 16-mm balloon to complete expansion of the stent graft apposition to the aortic wall, bridging the patient to definitive surgical repair.

Association of Marital Status in the Testing and Treatment of Sexually Transmitted Infections in the Emergency Department

Introduction Sexually transmitted infections (STIs) are frequently tested for and treated in the emergency department (ED). Age, race, and number of sexual partners are known risk factors for STIs. The objective of the current study was to examine marital status as it relates to testing and treating for STIs in the ED. Methods A database of 75,000 ED patient encounters from a single healthcare system in northeast Ohio between April 18, 2014, and March 7, 2017, was examined. All patients in the dataset underwent a urinalysis and urine culture or received STI testing in the ED. We performed Chi-square and multivariable regression analysis to examine the relationships between the patient's marital status and testing and treatment for STIs performed in the ED. Results There were 20,965 patient encounters where STI testing was performed and was analyzed. Patients were 9.1% (N=1,912) married, 86.6% (N=18,149) single, 4.0% (N=837) were neither married nor single, and 0.3% (N=67) with an unknown marital status. There were 7.1% (19/267) and 4.9% (12/267) of tested married men who were infected with gonorrhea and chlamydia, respectively, whereas only 0.4% (6/1,583) and 2.2% (35/1,588) of tested married women were infected with gonorrhea and chlamydia, respectively. Single men and women were both significantly more likely to have a positive test for gonorrhea and chlamydia compared to married men and women, respectively (P<0.001). Married men and women, compared to single men and women, respectively, were more likely to be given antibiotics for gonorrhea and chlamydia in the ED when the infection was present and not be given antibiotics for the infections when testing was negative (P<0.001). Single women (9.1%; 1,291/14,258) were more likely than married women (4.9%; 75/1,534) to have a positive test for trichomonas, but there were no significant differences between married (1.0%; 1/100) and single men (0.7%; 6/893). Conclusion Even when accounting for age and race, marital status can help predict infection with gonorrhea and chlamydia in the ED. The marital status could be considered by clinicians when risk stratifying patients regarding testing and treating for the diseases in the ED. Gonorrhea and chlamydia are much more common in single men and women and much less common in married persons. However, married men tested for gonorrhea and chlamydia were more than twice as likely to test positive for infection than married women. Married men and women were both more likely to be appropriately treated with antibiotics for gonorrhea and chlamydia in the ED (i.e., testing negative for infection and not receiving antibiotics or testing positive and receiving antibiotics) compared to non-married men and women. While trichomonas was more common in single women than married women, the infection was less common in men, and both married men and single men had similar rates of testing positive for the infection.

Vaginal leukocyte counts for predicting sexually transmitted infections in the emergency department

BACKGROUND

The use of vaginal white blood cell (WBC) counts to predict sexually transmitted infections (STIs) in the emergency department (ED) is incompletely characterized.

OBJECTIVES

Our objective was to assess the relationship between vaginal wet preparation WBC counts and STIs and to determine whether WBC counts of at least 11 WBCs per high-power field (HPF) could be useful for identifying STIs in women in the ED.

METHODS

Female ED patients 18 years or older who were evaluated in a single health system between April 18, 2014, and March 7, 2017, and had a genital wet preparation WBC result were retrospectively examined using univariable and multivariable analysis.

RESULTS

Vaginal wet preparation WBC counts were examined for 17,180 patient encounters. Vaginal WBC counts of at least 11 WBCs/HPF were associated with increased odds of having gonorrhea, chlamydia, or trichomoniasis. When this threshold was used for the diagnosis of each STI, sensitivity ranged from 48.2% to 53.9%, and specificity ranged from 67.2% to 68.8%.

CONCLUSION

Women with STIs are more likely to have higher vaginal WBC counts. However, higher vaginal wet preparation WBC counts in isolation have limited diagnostic utility for gonorrhea, chlamydia, and trichomoniasis. Incorporation of age, urine leukocyte esterase results, and vaginal WBC counts provided a better predictor of an STI than vaginal WBC counts alone.

A Descriptive Analysis of Men Diagnosed With Epididymitis, Orchitis, or Both in the Emergency Department

Introduction Epididymitis and orchitis are illnesses characterized by pain and inflammation of the epididymis and testicle. They represent the most common causes of acute scrotal pain in the outpatient setting. Epididymitis and orchitis have both infectious and noninfectious causes, with most cases being secondary to the invasive pathogens chlamydia, gonorrhea, and Escherichia coli (E.coli). The study's objective was to examine the epidemiology and clinical characteristics of men diagnosed with epididymitis or orchitis in a United States emergency department. Methods We examined a dataset of 75,000 emergency department (ED) patient encounters from a single health system in Northeast Ohio who underwent nucleic acid amplification testing (NAAT) for chlamydia, gonorrhea, or trichomonas, or who received a urinalysis and urine culture. All patients were ≥18 years of age, and all encounters took place between April 18, 2014, and March 7, 2017. The analysis only included men receiving an ED diagnosis of epididymitis, orchitis, or both. We evaluated laboratory and demographic data using univariable and multivariable analyses. Results There were 1.3% (256/19,308) of men in the dataset diagnosed with epididymitis, orchitis, or both. Only 50.1% (130/256) of men diagnosed with epididymitis, orchitis, or both were tested for gonorrhea and chlamydia during their clinical encounter, and among those 13.8% (18/130) were positive. Chlamydia (12.3% [16/130]) was more common than both gonorrhea (3.1% [4/129]) and trichomonas (8.8% [3/34]) among men <35 years of age diagnosed with epididymitis, orchitis, or both. Only 62.1% of men diagnosed with epididymitis, orchitis, or both received a urine culture, of which 20.1% grew bacteria at ≥10,000 CFU/ml. E. coli (N= 20) was the most common bacteria growing in urine culture followed by Streptococcus (N= 3), Klebsiella (N= 2), Pseudomonas (N= 2), and Serratia (N= 2). Men diagnosed with epididymitis, orchitis, or both who had a positive urine culture were more likely to be ≥35 years of age, married, had higher urine white blood cells (WBCs), more urine bacteria, higher urine leukocyte esterase, more likely to have urine nitrite, and were less likely to be empirically treated for gonorrhea and chlamydia (P≤.03 for all).  Conclusions In the ED, epididymitis, orchitis, or both are uncommonly diagnosed among patients undergoing genitourinary tract laboratory testing. Sexually transmitted infections (STIs) are common in men <35 years of age diagnosed with epididymitis, orchitis, or both, with chlamydia being most common. E. coli was the most common bacteria growing in urine culture.

Associations Between Bed Bugs and Mental Illness Among Emergency Department Patients

Background Bed bugs are common urban pests associated with stress, anxiety, depression, and some reports of suicidality. The emergency department (ED) treats patients with both acute mental illness and bed bug infestations. There have been few studies examining associations between bed bug infestations and mental illness. Methods A case-control study involving 332 adult ED patients infested with bed bugs and 4,952 uninfested control patients matched on sex, age (±1 year at the time of the ED visit), and the specific ED was completed. All clinic encounters occurred in northeast Ohio between February 1, 2011, and February 1, 2017, from a single health system. Univariable and multivariable regression analysis looked for associations between bed bug infestation and different psychiatric diagnoses and medications. Results Bed bug infested patients were more likely than uninfested patients to screen positive for an unsafe home and needing an abuse consult at ED triage (P≤.03 for both). ED psychiatric evaluations were not significantly more common among those with (2.4%) and without (1.3%) bed bugs (P=.14). Bed bug infested patients were significantly more likely to have an ED or inpatient diagnosis of alcohol abuse and psychosis (P≤.03 for both), but not for depression or suicidality. On univariable analysis, among ED patients not admitted to the hospital, bed bug infested patients were more likely to be diagnosed with psychosis or schizophrenia/schizoaffective disease (P≤.02) than uninfested patients. Among ED patients that received an ED or inpatient psychiatric evaluation and were admitted to the hospital, bed bug infested patients were significantly less likely to be diagnosed with depression and suicidality (P≤.03 for both). However, they were not significantly more likely to have insomnia or anxiety. Discussion Among ED patients, bed bug infestations were not associated with an ED or inpatient diagnosis of depression or suicidality. On univariable analysis, some mental health diagnoses such as anxiety and insomnia were more common among ED patients with bed bugs, but these associations were no longer significant on multivariable analysis. These associations likely reflect the complex relationships between socioeconomic factors, health disparities, mental illness, and having a bed bug infestation.

Association between bed bugs and allergic reactions

AIMS

To evaluate whether bed bugs are associated with allergic reactions in patients seen in the emergency department (ED).

METHODS AND RESULTS

This retrospective study included data from 9 EDs in Ohio between February 2011 and February 2017. The study comprised 332 patients with bed bug infestation matched 1:15 with 4952 control patients without bed bugs on the basis of age, sex and the presenting ED. Compared with uninfested patients, patients infested with bed bugs were more likely to have an ED or inpatient diagnosis of pruritus, hives or urticaria (odds ratio [OR], 9.12 [95% CI, 3.41-24.42]) and to be treated in the ED with an antihistamine (OR, 3.20 [95% CI, 1.87-5.50]) or albuterol (OR, 1.59 [95% CI, 1.07-2.36]) (P ≤ .02 for all). There were no significant differences in the rates of anaphylaxis and angioedema diagnosed in patients with and without bed bugs, which occurred in <1% in both groups.

CONCLUSION

Bed bug-infested patients are more likely to be diagnosed and treated for itchy cutaneous rashes, but are not clearly associated with more severe allergic reactions.

Descriptive analysis of prostatitis in the emergency department

INTRODUCTION

Prostatitis is one of the most common urologic diseases in ambulatory patients. However, prostatitis data are limited from the emergency department (ED) setting.

METHODS

A data set was examined of patients age 18 years or older who received urinalysis and urine culture or were tested for gonorrhea, chlamydia, or trichomonas in the ED from a health care system in northeast Ohio.

RESULTS

Of 19,308 ED encounters of male patients, 77 encounters (0.4%) involved the diagnosis of prostatitis. Men with prostatitis were younger (52.4 vs 66.3 years), were less likely to be hospitalized (27.3% vs 43.1%), had shorter clinical encounters (1336.5 vs 3019.3 min), and were less likely to arrive by emergency medical services or police (6.5% vs 45.5%) than men diagnosed with urinary tract infection (UTI) without prostatitis (n = 2527) (P ≤ .007 for all). Of the men with urinalysis, those with prostatitis had less bacteria (0.9+ vs 1.8+), blood (0.9+ vs 1.5+), glucose (4.0% vs 13.0%), leukocyte esterase (0.9+ vs 2.3+), nitrite positive (8.0% vs 21.4%), protein (0.5+ vs 1.2+), squamous epithelial cells (0.6 vs 1.7 per high-power field [HPF]), red blood cells (18.3/HPF vs 29.5/HPF), and white blood cells (31.6/HPF vs 57.6/HPF) than men diagnosed with UTI and no prostatitis (P ≤ .005 for all). Escherichia coli was the most common bacterium growing in the urine (58.8%; n = 10) and the blood (100.0%; n = 2) of men with prostatitis; however 73.0% (n = 17) of urine cultures and 90.9% (n = 22) of blood cultures had no bacterial growth. Of 77 patient encounters with prostatitis, 16 (20.8%) underwent testing for Neisseria gonorrhoeae and Chlamydia trachomatis and 3 (3.9%) for Trichomonas vaginalis. Of those tested, only 1 person was infected, with C trachomatis.

CONCLUSION

Prostatitis was uncommonly diagnosed in men undergoing urinalysis and urine culture or testing for sexually transmitted infections in the ED.

Epidemiologic and Clinical Characteristics of Tubo-Ovarian Abscess, Hydrosalpinx, Pyosalpinx, and Oophoritis in Emergency Department Patients

Introduction

Pelvic inflammatory disease (PID) is a spectrum of illness ranging from mild illness to more severe forms including tubo-ovarian abscess, hydrosalpinx, pyosalpinx, oophoritis (THPO). The objective of the study was to report rates and clinical characteristics of females presenting to the ED with a diagnosis of THPO in relationship to the presence or absence of sexually transmitted infections (STIs).

Methods

A database of ED patient encounters occurring from April 18, 2014, to March 7, 2017 was created. Analysis of women diagnosed with THPO and who had testing for gonorrhea, chlamydia, or trichomonas by nucleic acid amplification testing or who had a vaginal wet preparation was performed. Patient demographics, ED diagnoses, laboratory tests, medications administered in the ED, and medications prescribed were examined. Categorical variables were summarized as count and percentages and analyzed using the Chi-square test. Continuous variables were summarized as the mean and standard deviation and analyzed using the t-test. All statistical tests were two-sided with a significance level of 0.05.

Results

THPO was diagnosed in 0.3% (56/17,905) of patient encounters. There were 50% (28/56) of women with THPO admitted to the hospital. There were 25.0% (12/48) women who received a positive test result for Neisseria gonorrhoeae, Chlamydia trachomatis, and/or Trichomonas vaginalis. Women with THPO were significantly older, more likely to be infected with gonorrhea, and more likely to be diagnosed with sepsis and PID (P<.05 for all).

Conclusions

THPO is an infrequently encountered entity in the ED. A diagnosis of STI, PID, and sepsis can accompany these presentations. Although an uncommon diagnosis, ED providers must be attentive to patients presenting with pelvic symptoms that could be consistent with THPO to mitigate any complications that may arise and to direct the appropriate treatment.

Frequency of Coinfection on the Vaginal Wet Preparation in the Emergency Department

Introduction

Vaginal infections are common in the emergency department (ED) but the frequency of vaginal coinfections identified on wet preparation is unknown.

Methods

The study examined a data set of 75,000 ED patient encounters between April 18, 2014, and March 7, 2017, who had received testing for gonorrhea, chlamydia, or trichomonas or had received a urinalysis and urine culture during the ED encounter. From this data set we reviewed 16,484 patient encounters where a vaginal wet preparation was performed on women age 18 years and older. Findings from the vaginal wet preparation and ED discharge diagnoses were examined to evaluate the frequency of vaginal coinfections with vulvovaginal candidiasis, trichomoniasis, and bacterial vaginosis.

Results

Among the women who had wet preparations, 4,124 patient encounters (25.0%) had a diagnosis of bacterial vaginosis, 625 (3.8%) had a diagnosis of vulvovaginal candidiasis, and 1,802 (10.9%) were infected with Trichomonas vaginalis. Twenty encounters (0.1%) had a diagnosis of vulvovaginal candidiasis and trichomoniasis; 150 (0.9%), bacterial vaginosis and trichomoniasis; 136 (0.8%), vulvovaginal candidiasis and bacterial vaginosis; and 10 (0.1%), trichomoniasis, bacterial vaginosis, and vulvovaginal candidiasis. On vaginal wet preparation, the mean white blood cell count was 13.0 per high-power field. Clue cells were found in 6,988 wet preparations (42.4%); 1,065 wet preparations (6.5%) had yeast and 1,377 (8.4%) had T. vaginalis. T. vaginalis was identified in 2.5% (266/10,542) of urinalyses and 8.4% (406/4,821) of nucleic acid amplification tests.

Conclusions

Vaginal coinfections were uncommon among women receiving a vaginal wet preparation in the emergency department. The most common vaginal coinfection was bacterial vaginosis and trichomonas.

Bed bugs are associated with anemia

INTRODUCTION

Bed bugs are hematophagous insects that can be problematic in some urban emergency departments. The objective was to determine if red blood cell (RBC) and coagulation indices of bed bug-infested emergency department (ED) patients differed from those of noninfested control patients.

METHODS

A chart review from a single health system was performed for ED patients between February 1, 2011, and February 1, 2017. Bed bug-infested patients were matched to noninfested control patients on the basis of age, sex, and the presenting ED. Variables were analyzed with the t-test and Pearson χ² test and were modeled with multivariable logistic regression.

RESULTS

The study had 332 bed bug-infested patients and 4952 controls. Infested patients had lower hemoglobin (11.7 g/dL vs 12.8 g/dL), hematocrit (35.0% vs 37.9%), RBC counts (4.1 × 10⁹/L vs 4.4 × 10⁹/L), mean corpuscular volume (86.0 vs 87.5 fL/cell), and mean corpuscular hemoglobin concentrations (33.2 vs 33.7 g/dL) and higher RBC distribution width-coefficient of variation (RDW-CV) (15.2% vs 14.2%) than noninfested patients (all P ≤ .003). Infested patients were more likely to be anemic (59.5% vs 36.9%) and to have severe anemia (4.4% vs 0.7%) (P < .001 for both). Blood transfusions were more common in those with bed bugs (5.1%) than those without bed bugs (2.3%) (P < .001).

CONCLUSION

Bed bug infestated patients in the ED are associated with anemia.

Descriptive Evaluation of Male Emergency Department Patients in the United States With Gonorrhea and Chlamydia

Introduction

Sexually transmitted infections are commonly tested for in the emergency department (ED), but diagnostic test results are often unavailable during the clinical encounter.

Methods

We retrospectively reviewed health records of 3,132 men ≥18 years that had an emergency department visit in northeast Ohio between April 18, 2014 and March 7, 2017. All subjects underwent testing for Neisseria gonorrhoeae and Chlamydia trachomatis. Independent t-tests and chi-square analyses were performed as well as multivariable regression analysis.

Results

On univariable analysis, men with N gonorrhoeae and/or C trachomatis, compared with uninfected men, were younger (25.9 vs 32.4 years), more likely to be of Black race (91.7% vs 85.6%), less likely to be married (3.7% vs 10.2%), less likely to arrive to the ED by ambulance or police (1.7% vs 4.1%), and more likely to be diagnosed with a urinary tract infection (8.3% vs 3.7%), to be treated for gonorrhea and chlamydia in the ED (84.6% vs 54.9%), and to have higher emergency severity index (ESI) scores (3.8 vs 3.6) (P ≤ .03 for all). On urinalysis, men infected with N gonorrhoeae and/or C trachomatis had significantly more white blood cells (55.1 vs 20.9); more mucus (1.3 vs 1.2); higher leukocyte esterase (1.5 vs .4); fewer squamous epithelial cells (.6 vs 1.4); higher urobilinogen (1.1 vs .8); higher bilirubin (.09 vs .05); and more protein (.4 vs .3) (P ≤ .04).

Conclusions

Demographic and urinalysis findings can be associated with an increased odds of men being infected with N gonorrhoeae and/or C trachomatis.

Artificial Intelligence-Enabled ECG Algorithm to Identify Patients With Left Ventricular Systolic Dysfunction Presenting to the Emergency Department With Dyspnea

BACKGROUND

Identification of systolic heart failure among patients presenting to the emergency department (ED) with acute dyspnea is challenging. The reasons for dyspnea are often multifactorial. A focused physical evaluation and diagnostic testing can lack sensitivity and specificity. The objective of this study was to assess the accuracy of an artificial intelligence-enabled ECG to identify patients presenting with dyspnea who have left ventricular systolic dysfunction (LVSD).

METHODS

We retrospectively applied a validated artificial intelligence-enabled ECG algorithm for the identification of LVSD (defined as LV ejection fraction ≤35%) to a cohort of patients aged ≥18 years who were evaluated in the ED at a Mayo Clinic site with dyspnea. Patients were included if they had at least one standard 12-lead ECG acquired on the date of the ED visit and an echocardiogram performed within 30 days of presentation. Patients with prior LVSD were excluded. We assessed the model performance using area under the receiver operating characteristic curve, accuracy, sensitivity, and specificity.

RESULTS

A total of 1606 patients were included. Median time from ECG to echocardiogram was 1 day (Q1: 1, Q3: 2). The artificial intelligence-enabled ECG algorithm identified LVSD with an area under the receiver operating characteristic curve of 0.89 (95% CI, 0.86-0.91) and accuracy of 85.9%. Sensitivity, specificity, negative predictive value, and positive predictive value were 74%, 87%, 97%, and 40%, respectively. To identify an ejection fraction <50%, the area under the receiver operating characteristic curve, accuracy, sensitivity, and specificity were 0.85 (95% CI, 0.83-0.88), 86%, 63%, and 91%, respectively. NT-proBNP (N-terminal pro-B-type natriuretic peptide) alone at a cutoff of >800 identified LVSD with an area under the receiver operating characteristic curve of 0.80 (95% CI, 0.76-0.84).

CONCLUSIONS

The ECG is an inexpensive, ubiquitous, painless test which can be quickly obtained in the ED. It effectively identifies LVSD in selected patients presenting to the ED with dyspnea when analyzed with artificial intelligence and outperforms NT-proBNP. Graphic Abstract: A graphic abstract is available for this article.

The Impact of an Emergency Department Upgrade to Level I Trauma Status on the Timeliness of Nontrauma Computed Tomography Scans

BACKGROUND

Resources such as computed tomography (CT) scanners are sometimes shared when separate adult and pediatric emergency departments (EDs) exist in proximity.

OBJECTIVES

To assess the impact of American College of Surgeons Level I trauma verification of an adult ED on the timeliness of nontrauma CT scans in a pediatric and adult ED that share a CT scanner.

METHODS

ED patient records were retrospectively reviewed to determine the time from order to completion of nontrauma CT scans. We compared the timeliness of CT scan completion between the year leading up to the adult ED being verified as a Level I Trauma Center (2015), and the 2 subsequent years (2016-2017).

RESULTS

The median time for nontrauma CT completion in the adult ED prior to Level I verification was 39 min, compared with 50 min and 49 min for the subsequent 2 years (p < 0.001). Similarly, the median time for completion of nontrauma CT scans in the pediatric ED increased from 33 min to 41 min and 39 min (p < 0.001). The proportion of patients who received CT scans within 30 min from order decreased after adult ED trauma upgrade, from 40% in 2015 to 30% and 32% (p < 0.001) in the 2 subsequent years. The pediatric ED showed similar results, with 48% of patients receiving CT scans within 30 min in 2015, compared with 34% in 2016 and 35% in 2017 (p < 0.001).

CONCLUSIONS

Level I trauma verification of the adult ED adversely affected the timeliness of nontrauma CT scans in the EDs.

Human immunoglobulin G responses to Cimex lectularius L. saliva

AIMS

To investigate the immunoglobulin (Ig) G response after being fed upon by Cimex lectularius L.

METHODS AND RESULTS

Participants were fed upon by three male C lectularius insects weekly for a month. Blood was obtained before the feeding and at the last feeding, which was used for immunoblots against bed bug salivary gland extract, with antihuman Immunoglobulin G (IgG) secondary antibodies. No consistent IgG changes developed in 11 humans serially fed upon by C lectularius. Two participants had new IgG responses to proteins at molecular weights of approximately 12-13 kDa, and one had an IgG response to a protein at approximately 40 kDa. At the last study visit, more intense IgG bands to proteins at molecular weights of 12-13 kDa had developed in 55% of participants (6/11) and at molecular weights of ≈30, ≈40 and ≈70 kDa in 45% (5/11) compared with the first study visit. Nitrophorin and apyrase were the most common C lectularius proteins identified with liquid chromatography-tandem mass spectrometry in both crushed bed bug salivary gland extract and post-bed bug feeding extract.

CONCLUSIONS

Human participants did not have consistent IgG responses to crushed C lectularius salivary gland extract.

Knowledge, Experience, and Concerns Regarding Bed Bugs Among Emergency Medical Service Providers

Introduction

Bed bugs are commonly encountered by emergency medical service (EMS) providers. The objective of this study was to determine the frequency with which EMS providers encountered bed bugs, assess their knowledge about bed bugs, and analyze the actions they take after finding bed bugs.

Methods

We anonymously surveyed 407 EMS providers from 180 EMS agencies in northeast Ohio between September 1, 2018, through March 31, 2019.

Results

Among the providers surveyed, 21% (n = 84) of the EMS providers reported seeing bed bugs at least monthly, and 6% (n = 24) reported seeing bed bugs at least weekly. Being younger, male, and working in an urban environment (vs. rural) were associated with EMS providers reporting more frequent bed bug encounters (p: ≤.05). The mean level of concern for encountering bed bugs among EMS providers was 3.54 (SD: 1.15; scale: 1 = no concern, 5 = very concerned). Among the EMS providers who reported seeing bed bugs at least monthly, 30% took the affected EMS stretcher out of service when they encounter a bed bug, 43% took the EMS rig out of service, 83% cleaned the EMS stretcher with a disinfectant, and 88% notified the ED that their patient has bed bugs. EMS providers scored poorly (mean: 69% correct responses) in a seven-question assessment of basic bed bug biology and public health.

Conclusion

Based on our findings, we concluded that EMS knowledge and behavior related to bed bugs are suboptimal.

Association of Bartholin cysts and abscesses and sexually transmitted infections

INTRODUCTION

Bartholin gland cysts or abscesses account for many gynecologic visits in the emergency department (ED). Previous smaller studies have suggested a link between Bartholin cysts/abscesses and sexually transmitted infections (STIs), but few studies have involved the ED.

METHODS

We retrospectively identified patients aged 18 years or older seen in 1 ED between January 2012 and March 2017 who had urinalysis and urine culture and/or were tested for gonorrhea, chlamydia, or trichomonas by nucleic acid amplification testing. Univariate and multivariate analyses were used to evaluate associations between Bartholin cysts/abscess and demographics, laboratory findings, and ED diagnoses.

RESULTS

Data were collected for 75,000 ED patients; 64 patients had a diagnosis of Bartholin cyst or abscess, 40 of whom were also tested for Neisseria gonorrhoeae or Chlamydia trachomatis. Ten percent of patients with a Bartholin cyst/abscess were infected with N gonorrhoeae, compared with 3% of those without a Bartholin cyst/abscess (P = .008). The rates of C trachomatis and Trichomonas vaginalis infections were 13% and 26%, respectively, among patients with a Bartholin cyst/abscess, compared with 8% and 30%, respectively, among those without a Bartholin cyst/abscess (P > .05 for both). On regression analysis, only increased urobilinogen level (β, 0.31; odds ratio, 1.36; 95% CI, 1.11-1.66; P = .003) and infection with N gonorrhoeae (β, 1.69; odds ratio, 5.40; 95% CI, 1.43-20.35; P = .01) were associated with a Bartholin cyst/abscess.

CONCLUSIONS

Clinicians in the ED should consider testing patients with a Bartholin cyst/abscess for gonorrhea.

A Preliminary Report Showing Spinosad and Fluralaner Are Able to Incapacitate Cimex lectularius L., the Common Bed Bug

Cimex lectularius L., the common bed bug, is a hematophagous human ectoparasite. The veterinary drugs, spinosad and fluralaner, were studied for their ability to incapacitate C. lectularius when administered in a blood meal using an artificial feeding system under laboratory conditions. Tested drug doses were based on the reported peak blood levels in animals given the drugs. Spinosad at doses 1,000 ng/mL or higher resulted in 75% or greater bed bug incapacitation (defined as death or immobility). Fluralaner at doses 500 ng/mL or higher had 100% bed bug incapacitation. Both drugs were significantly more effective than controls at these doses (P < 0.001).

Patient Preference for Medical Information in the Emergency Department: Post-Test Survey of a Random Allocation Intervention

INTRODUCTION

Health literacy can create barriers for ED staff attempting to communicate important information to patients. Video discharge instructions may address some of these barriers by improving patients' comprehension of medical information and addressing health literacy challenges.

METHODS

One hundred ninety-six patients diagnosed with either hypertension, asthma, congestive heart failure, or diabetes were randomly assigned to 1 of 2 interventions: watching video medical information followed by reviewing written discharge instructions or written instructions first, followed by video education. After the interventions, patients from both groups completed surveys assessing their preferences for receiving medical information.

RESULTS

We found that 44% (n = 86/196) of ED patients preferred receiving medical information in video format, whereas 18% (n = 35/196) favored the written format, and 38% (n = 75/196) of the sample preferred receiving both formats. Fifty-five percent of men (n = 38/69) preferred the video format, whereas 42% (n = 51/122) of women indicated a preference for both video and written formats. Learning something new from the video was associated with patient preference for receiving medical instructions, (χ2 [1] = 9.39, P = 0.01) and the desire to watch medical videos or read information at home via the Internet (χ2 [1] = 18.46, P < 0.001).

DISCUSSION

The majority of ED patients in this study preferred medical information in video or video plus written formats, compared with written-only format.

Ivermectin and Moxidectin Can Incapacitate Different Strains of the Common Bed Bug Cimex lectularius L.: A Study

The common bed bug Cimex lectularius L. (C. lectularius) is a hematophagous ectoparasite that has recently resurged in many western industrialized nations, in part due to pesticide resistance. Using a laboratory feeding system, we found that the antiparasitic drugs ivermectin and moxidectin did not show higher incapacitation rates in pyrethroid-resistant strains of C. lectularius compared to a pyrethroid-susceptible strain. Additionally, we developed a high-performance liquid chromatography (HPLC) and mass spectroscopy (MS) assay to measure the concentrations of ivermectin inside C. lectularius and found that ivermectin persists in the insects for up to one month. HPLC/MS will be useful in understanding the pathophysiology behind the long-term morbidity observed in C. lectularius that consumes a sublethal dose of ivermectin.

Body lice and bed bug co-infestation in an emergency department patient, Ohio, USA

Body lice and bed bugs are hematophagous insects that parasitize humans. Body lice are established vectors of several bacterial pathogens (e.g. Bartonella quintana, Borrelia recurrentis). Bed bugs are biologically competent vectors of some of the same agents, but their vectorial capacity for these in nature is unclear. In particular, a lack of exposure to louse-borne pathogens in bed bugs in the field could be a factor that limits their contribution to transmission. Here, we describe a case of a patient seen in an urban emergency department who was suffering from infestation with both body lice and bed bugs. Insects were collected from the patient and tested for the presence of louse-borne bacterial pathogens using 16S rRNA gene amplicon sequencing. Although no Bartonella, Borrelia, or Rickettsia were detected, this case provides evidence of ecological overlap between body lice and bed bugs and highlights several potential risk factors for co-infestation. The ecological relationships between bed bugs, body lice, and louse-borne bacteria should be further investigated in the field to determine the frequency of co-infestations and identify possible instances of pathogen infection in bed bugs.

Molecular detection of Rickettsia infection in field-collected bed bugs

Bed bugs are now one of the most prevalent human-associated, blood-feeding pests in the urban world, but few studies of their association with human pathogens have been conducted since their resurgence. Here, we used PCR to screen samples of field-collected bed bugs (Cimex spp.) for the presence of Rickettsia bacteria and we describe the first detection of an uncharacterized Rickettsia in Cimex lectularius in nature. Rickettsia was detected in 5/39 (12.8%) of the bed bug samples tested. In particular, three pools from the USA and two individual insects from the UK were positive for Rickettsia DNA. Sequencing and analysis of a fragment of the citrate synthase gene (gltA) from positive samples from each country revealed that the Rickettsia detected in both were identical and were closely related to a Rickettsia previously detected in the rat flea Nosopsyllus laeviceps. Additional experiments indicated that the Rickettsia localizes to multiple tissues in the bed bug and reaches high titres. Attempts were made to infect mammalian cells in culture but these efforts were inconclusive. Our findings suggest that Rickettsia are secondary endosymbionts of bed bugs and have potential implications for both bed bug control and public health. However, further investigation is required to determine the pathogenicity of this Rickettsia, its transmission mechanisms, and its contributions to bed bug physiology.

History, Physical Examination, and Laboratory Findings Associated with Infection and the Empiric Treatment of Gonorrhea and Chlamydia of Women in the Emergency Department

Background Neisseria gonorrhea (NG), Chlamydia trachomatis (CT), and Trichomonas vaginalis (TV) are common sexually transmitted infections (STIs) treated in the emergency department (ED). Objectives To assess the history, physical examination, and laboratory findings associated with NG and CT infection and the decision to administer empiric antibiotic treatment for the diseases in the ED. Methods A retrospective review of 566 clinical encounters of adult female patients tested for STIs between January 1, 2013 and December 31, 2014. An analysis of patient- and provider-level variables was assessed to determine the characteristics associated with empiric antibiotic treatment in the ED and post-discharge laboratory confirmed NG or CT. Results Younger age and the presence of TV on vaginal wet prep had a higher association with being infected with NG or CT (p < 0.05). Subjective exam findings, such as vaginal discharge, abdominal pain, urinary urgency, urinary frequency, dysuria, objective vaginal discharge, cervical motion tenderness, adnexal tenderness, vaginal bleeding, as well as positive leukocyte esterase and nitrites on urinalysis were all not associated with NG or CT infection (p > 0.05). ED providers were more likely to treat subjects in the ED for NG and CT when there was subjective and objective vaginal discharge, cervical motion tenderness, adnexal tenderness, and vaginal bleeding, TV on wet prep, and leukocyte esterase on urinalysis (p < 0.05). Conclusions Only younger age women and the presence of TV on vaginal wet prep were associated with NG or CT infection. ED providers empirically over-treated with antibiotics ~20 patients uninfected with NG and CT by laboratory confirmation, for every one patient with a laboratory confirmed infection.

The Benefit of a Single Oral Dose of Ivermectin in Humans: The Adverse Effects on Cimex lectularius L. Populations and Fecundity

Objective

To measure the population size and fecundity of the common bed bug Cimex lectularius L. (C. lectularius) after feeding it with the blood obtained from human subjects who have consumed a single dose of ivermectin.

Methods 

Serial blood samples were obtained from two human subjects at hour 0 (control) and 4-96 hours after they received a single 0.2 mg/kg dose of ivermectin. The blood samples were then fed to 2,273 bed bugs. Bed bug incapacitation rates, fecundity, and population sizes were recorded over a 54-day period. Whole blood ivermectin levels were measured in the human subjects and the insects.

Results 

The fold change in the size of the control group population over the course of the experiment was found to be 2.16. This was significantly greater (p: <.001) than for all the post-ivermectin feeding groups (range: -11.04-1.43). Two weeks after the experiment, the number of eggs laid per live adult female bed bug per day was 10.74 for controls, which was significantly different (p: <0.001) compared to all the post-ivermectin feeding groups (range: 0-4.28).

Conclusions 

There were significant reductions in C. lectularius population size and fecundity in insects that fed on blood obtained from human study subjects up to 96 hours after they have consumed a single oral dose of ivermectin.

Cimicosis in Persons Previously Fed Upon by Bed Bugs

Introduction

Bed bug infestations have risen dramatically in many industrialized nations in recent decades. Most people fed upon by bed bugs will develop a pruritic rash although the frequency with which this occurs is not definitively known and may depend on host factors including the duration of the infestation.

Methods

Surveys were completed from 706 emergency department (ED) patients in Cleveland, OH about their current and past exposure with bed bugs. Subjects were asked about any post-bed bug feeding rashes that developed.

Results

There were 24% (169/698) of subjects reporting either a current or past home bed bug infestation, with 37% (253/698) reporting they had previously been fed upon by a bed bug. Of those reporting a previous bed bug feeding, 68% (172/253) reported a pruritic post-bed bug feeding rash and 24% (57/237) reported developing a blister. Overall, 5% (37/705) of ED patients reported currently having a rash, but only 2% (14/698) of ED patients reported currently have bed bugs at home and of those, only 14% (2/14) said they currently had a rash.

Conclusion

While 68% of ED patients reported a pruritic post-bed bug feeding pruritic rash, almost a third of persons did not report developing the rash. Post-bed bug feeding blister reactions are less common. Asking ED patients about a rash had a low sensitivity of 14% (2-43%) and a specificity 95% (93-96%) to identify persons reporting home bed bugs.

Xenointoxication of a Rabbit for the Control of the Common Bed Bug Cimex lectularius L. Using Ivermectin

Human bed bug infestations have undergone a recent global resurgence. The human antiparasitic drug ivermectin has been proposed as a strategy to help control bed bug infestations, but in vivo data are lacking. We allowed separate populations of the common bed bug, Cimex lectularius L., to feed once on a rabbit before and after it was injected subcutaneously with 0.3 mg/kg of ivermectin, and bed bug morbidity and mortality were recorded. Ivermectin levels in the rabbit were measured using high-performance liquid chromatography and mass spectroscopy. Ivermectin blood levels of ∼2 ng/mL caused reductions in bed bug fecundity, and levels of >8 ng/mL caused bed bug death and long-term morbidity including reductions in refeeding, mobility, reproduction, and molting. Gut bacterial cultures from the fed bed bugs showed that ivermectin altered the bed bug gut microbiome.

Spontaneous methicillin-resistant Staphylococcus aureus (MRSA) meningitis

Spontaneous methicillin-resistant Staphylococcus aureus (MRSA) meningitis is extremely rare and has a high mortality rate. We report a case of MRSA meningitis in an otherwise healthy young adult female with no recent trauma or neurosurgical interventions. Despite antibiotics she suffered a vasculitis-induced cerebral vascular ischemic event.

Proton Pump Inhibitor Use Is Associated With a Reduced Risk of Infection with Intestinal Protozoa

OBJECTIVE

Proton pump inhibitors (PPIs) can kill some human protozoan parasites in cell culture better than the drug metronidazole. Clinical data showing an antiprotozoal effect for PPIs are lacking. The objective of the study is to determine if PPI use is associated with a reduced risk of having intestinal parasites.

METHODS

We obtained electronic medical record data for all persons who received a stool ova and parasite (O & P) examination at our tertiary care academic medical center in Cleveland, Ohio, between January 2000 and September 2014. We obtained the person's age, whether they were taking a PPI at the time of the O & P examination, and whether the pathology report indicated the presence of any parasites. χ² with Yates correction was used to determine if PPI use was associated with stool protozoa.

RESULTS

Three intestinal protozoa were identified in 1199 patients taking a PPI (0.3%), and 551 intestinal parasites were identified in the 14,287 patients not taking a PPI (3.9%). There was a statistically significant lower likelihood of finding protozoa in the stool of a person taking a PPI compared with those not taking a PPI (P < .0001).

CONCLUSIONS

Patients taking a PPI were statistically less likely to have an intestinal protozoa reported on stool O & P examination compared with those not taking a PPI.

Emergency Medicine Resident Assessment of the Emergency Ultrasound Milestones and Current Training Recommendations

OBJECTIVES

Emergency ultrasound (EUS) has been recognized as integral to the training and practice of emergency medicine (EM). The Council of Emergency Medicine Residency-Academy of Emergency Ultrasound (CORD-AEUS) consensus document provides guidelines for resident assessment and progression. The Accredited Council for Graduate Medical Education (ACGME) has adopted the EM Milestones for assessment of residents' progress during their residency training, which includes demonstration of procedural competency in bedside ultrasound. The objective of this study was to assess EM residents' use of ultrasound and perceptions of the proposed ultrasound milestones and guidelines for assessment.

METHODS

This study is a prospective stratified cluster sample survey of all U.S. EM residency programs. Programs were stratified based on their geographic location (Northeast, South, Midwest, West), presence/absence of ultrasound fellowship program, and size of residency with programs sampled randomly from each stratum. The survey was reviewed by experts in the field and pilot tested on EM residents. Summary statistics and 95% confidence intervals account for the survey design, with sampling weights equal to the inverse of the probability of selection, and represent national estimates of all EM residents.

RESULTS

There were 539 participants from 18 residency programs with an overall survey response rate of 85.1%. EM residents considered several applications to be core applications that were not considered core applications by CORD-AEUS (quantitative bladder volume, diagnosis of joint effusion, interstitial lung fluid, peritonsillar abscess, fetal presentation, and gestational age estimation). Of several core and advanced applications, the Focused Assessment with Sonography in Trauma examination, vascular access, diagnosis of pericardial effusion, and cardiac standstill were considered the most likely to be used in future clinical practice. Residents responded that procedural guidance would be more crucial to their future clinical practice than resuscitative or diagnostic ultrasound. They felt that an average of 325 (301-350) ultrasound examinations would be required to be proficient, but felt that number of examinations poorly represented their competency. They reported high levels of concern about medicolegal liability while using EUS. Eighty-nine percent of residents agreed that EUS is necessary for the practice of EM.

CONCLUSIONS

EM resident physicians' opinion of what basic and advanced skills they are likely to utilize in their future clinical practice differs from what has been set forth by various groups of experts. Their opinion of how many ultrasound examinations should be required for competency is higher than what is currently expected during training.

Schistosoma haematobium infection is associated with increased urine foam

We compared urine microscopy and dipstick results for urine foam from 59 children in a Schistosoma haematobium-endemic area in a blinded manner. The sensitivity and specificity, respectively, for diagnosing S. haematobium compared with microscopy was: 74% and 72% for the shake test; 61% and 97% for microscopic hematuria; and 43% and 83% for proteinuria. When >17 eggs/10 mL urine was detected on microscopy, the sensitivity and specificity, respectively, were: 100% and 72% for the shake test; 90% and 97% for microscopic hematuria; and 80% and 83% for proteinuria. Urine foam height >34 mL was significantly more likely to have S. haematobium eggs detected on microscopy (P = 0.001) than urine foam ≤34 mL, indicating that S. haematobium-infected urine is associated with increased urine foam.

The use of ivermectin to kill ixodes scapularis ticks feeding on humans

OBJECTIVE

The purpose of this study was to determine whether 400 µg/kg oral ivermectin is able to kill Ixodes scapularis nymphs and adult female ticks feeding on humans.

METHODS

Ten study subjects each wore 2 ostomy bags, the one containing 24 I scapularis nymphs, and the other containing 24 I scapularis adult females. Twenty-four hours after the ostomy bags were attached, study subjects received either 400 µg/kg ivermectin or placebo. Thirty hours after the ivermectin or placebo was consumed, the ticks were removed, and mortality determined in a double-blinded manner.

RESULTS

Eleven percent of the I scapularis nymphs attached in the ivermectin group compared with 17% in the placebo. Mortality for the I scapularis nymphs that attached at the time of removal was 55% in the ivermectin group and 47% in the placebo group. Mortality for the I scapularis nymphs 5 days after removal was 92% in the ivermectin group and 88% for the placebo. Three percent of the I scapularis adults attached in the ivermectin group compared with 9% in the placebo group. Mortality for I scapularis adults was 0% on day 3 and 33% on day 8 for both the ivermectin and placebo groups. There were statistically insignificant differences in the mortality rates between I scapularis nymphs and adults exposed to ivermectin or placebo.

CONCLUSIONS

There were a high number of ticks that died in both groups but the data do not support our hypothesis that ivermectin can kill I scapularis. The study was not designed to determine whether it could prevent the transmission of tick-borne illness.

Initial assessment of the ability of ivermectin to kill Ixodes scapularis and Dermacentor variabilis ticks feeding on humans

OBJECTIVE

The purpose of this study was to determine Ixodes scapularis and Dermacentor variabilis tick mortality when fed on humans who have consumed 400 μg/kg oral ivermectin.

METHODS

Six study subjects, 3 in each group, were randomly assigned to receive either 400 μg/kg ivermectin or placebo in a blinded manner. After consuming either ivermectin or placebo, each study subject had 2 colostomy bags attached to his or her abdomen. One of the colostomy bags contained 7 I scapularis nymphs and 7 adults. The other colostomy bag contained 7 D variabilis nymphs and 7 adults. Tick mortality was recorded over the next 24 hours.

RESULTS

Fifty-five percent (6 of 11) of the attached I scapularis nymphs exposed to ivermectin had morbidity (3 of 11) or died (3 of 11), compared with 0% morbidity and mortality in the 2 I scapularis nymphs that attached in the placebo group. No I scapularis adults or D variabilis nymphs attached to feed. Among D variabilis adults that attached to feed, there was a 0% mortality rate for both the placebo group (0 of 6) and the ivermectin group (0 of 8).

CONCLUSIONS

We demonstrate a novel method to confine ticks to human subjects to study tick-borne diseases. While there was a trend toward I scapularis morbidity and mortality in the ivermectin arm, the low number of ticks that attached in the placebo group limited our analysis. Most ticks began feeding in the last 12 hours of the experiment, significantly limiting their exposure to ivermectin. Ivermectin does not cause early death in D variabilis adults.