Does choice of anesthesia during stage 1 sacral neuromodulation testing influence outcomes?

INTRODUCTION

Staged sacral neuromodulation (SNM) testing has been shown to have a high rate of progression to permanent implantation for the management of voiding dysfunction. Stage 1 lead placement (SNM-I) can be performed under monitored anesthesia care (MAC) or general anesthesia (GA). MAC allows for interpretation of sensory and motor responses to optimize lead placement while GA only permits for motor assessment. However, patient discomfort and movement can make lead placement challenging during MAC. Herein we evaluate whether the anesthesia type impacts the progression rate to permanent implantation (SNM-II).

MATERIALS AND METHODS

A retrospective chart review was performed for patients who underwent SNM-I in the operating room for wet overactive bladder between 2005 and 2023. Patients were divided into two groups based on the type of anesthesia used, MAC or GA. Clinical variables and progression to SNM-II were compared between cohorts. Progression to SNM-II was based on ≥50% symptomatic improvement during a 1-2 week trial period following SNM-I.

RESULTS

Of 121 patients included in the study, 95 (79%) underwent MAC and 26 (21%) GA for SNM-I. No difference in the progression rate to SNM-II was noted between groups (MAC, 68/95 patients, 72%; GA, 19/26, 73%; p = 0.39). We also found no difference when comparing the GA group to the 26 most recent MAC patients (MAC, 20/26 patients, 77%; GA, 19/26, 73%; p = 0.48).

CONCLUSION

Types of anesthesia for SNM-I did not affect rate of progression to SNM-II. The result lends support to the reliance on motor responses alone for lead placement during SNM-I.

Stigmatization as a Barrier to Urologic Care: A Review

Heavy societal stigma of certain conditions has created an environment where individuals may be hesitant to seek professional care. Urology is a specialized field that focuses on many of these conditions that society has deemed taboo to discuss. In this review, we address barriers that have prevented patients from seeking urologic care in order to better understand and elucidate important concerns within development of the physician-patient relationship. Recognizing these concerns can also assist in public health outreach approaches to motivate patients for seeking urologic care. The scope of this review was limited to three highly prevalent conditions affecting both men and women, including urinary incontinence, erectile dysfunction, and genitourinary syndrome of menopause.

Lower Urinary Tract Symptoms in Depression: A Review

Lower Urinary Tract Symptoms (LUTS) are frequently present in the general population as patients age with approximately a third of individuals experiencing LUTS during their lifetime. LUTS can be further defined as having any of the following symptoms: urinary hesitancy, straining, nocturia, increased urination frequency, and dysuria. LUTS has the potential for patients to contribute their symptoms to what can normally occur as we age. This can lead to a decrease in patients seeking care and could negatively impact patients' health-related quality of life (HRQL). In conjunction with LUTS, we obtained from our analysis that LUTS and depression are closely related and worsening depressive symptoms may increase the severity of LUTS. We also discerned three categories of factors that can yield major depression namely adversity, internalizing, and externalizing factors. Within these categories, trauma, social support, genetic factors, and minimal education appeared to increase the risk of depression in patients. With the recent increase in mental health awareness and more access to mental health care amid the COVID-19 Pandemic, further screening, and collaboration between providers to treat both urological and psychiatric symptoms could improve patient outcomes. It is important for providers to have an increased understanding of the mental and physical impact both LUTS and depression can have on patients' wellbeing. This has the potential to help patients be more open about their symptoms with the aim of better addressing LUTS and depression to positively impact their HRQL.

Koro Syndrome: Epidemiology, Psychiatric and Physical Risk Factors, Clinical Presentation, Diagnosis, and Treatment Options

Koro syndrome is a multi-tiered disease presenting as an overwhelming belief that one's sex organs are shrinking into their body. Moderate to severe anxiety attacks are associated with the condition, along with a fear of imminent death. Koro is often culturally related and is most seen as an epidemic form in East and Southeast Asia, although it can present anywhere worldwide in its sporadic form. The condition typically affects young males who believe in sex-related myths, and many individuals can co-present with anxiety, depression, or even psychosis. Although most presentations of Koro are self-limiting, the condition is harmful for one's self-esteem and quality of life, and some individuals may go through extreme, physically injurious measures to prevent genital retraction. Treatments include the use of psychotherapy that has a sex education component, especially if the patient believes in culturally rooted myths. In sporadic Koro, it is believed that if the primary psychiatric disorder is treated with anxiolytics, antidepressants, sedatives, or psychotics, the secondary Koro-like symptoms will also fade. Additional investigation on the prevalence, pathogenesis, factors that correlate with treatment efficacy are needed to fully understand Koro syndrome.

Vasectomy Regret Among Childless Men

OBJECTIVE

To address historical concerns surrounding vasectomy in childless men, we sought to evaluate for the level of regret in this unique cohort.

METHODS

The records of patients who underwent vasectomy via single surgeon between 2006 and 2021 were retrospectively reviewed and those who had not fathered children in any capacity at time of vasectomy were selected. We devised a 6-question survey inquiring about regret and thoughts on vasectomy reversal and assisted reproductive technology (ART). The questions are listed in Table 1. Patients were queried via a telephone call to rate their level of regret, both immediately after vasectomy and present day. The cohort was analyzed via age at time of vasectomy, time since vasectomy and marital status.

RESULTS

There were 4812 overall patients who underwent vasectomy in this interval, with 205 (4.3%) who were childless. The response rate was 33.2% (68/205). Average age was 36.6 years with average time since vasectomy at time of phone call was 5.51 years. Regret rate was 4.4% immediately following vasectomy and 7.4% at time of telephone interview. A confirmatory, second consultation before vasectomy was present in 6.8% (14/205). The majority of patients 150/205 (73.1%) were married. When patients were stratified by marital status, there was no significant difference in any of the questions. The majority of patients were satisfied with their decision, with few contemplating or pursuing reversal or ART (Table 1).

CONCLUSION

Regret in childless patients who undergo vasectomy is very rare, with the majority of patients feeling that their life was improved.

Testosterone Replacement Therapy in the Treatment of Depression

BACKGROUND

Depression is a common disorder that affects millions globally and is linked to reduced quality of life and mortality. Its pathophysiology is complex and there are several forms of treatment proposed in the literature with differing side effect profiles. Many patients do not respond to treatment which warrants augmentation with other treatments and the investigation of novel treatments. One of these treatments includes testosterone therapy which evidence suggests might improve depressed mood in older patients with low levels of testosterone and helps restore physical impairments caused by age-related hormonal changes.

OBJECTIVE

The objective of this review is to synthesize information regarding clinical depression, its treatment options, and the efficacy and safety of testosterone treatment for the treatment of depression.

METHODS

This review utilized comprehensive secondary and tertiary data analysis across many academic databases and published work pertaining to the topic of interest.

RESULTS

Within some subpopulations such as men with dysthymic disorder, treatment resistant depression, or low testosterone levels, testosterone administration yielded positive results in the treatment of depression. Additionally, rodent models have shown that administering testosterone to gonadectomized male animals reduces symptoms of depression. Conversely, some studies have found no difference in depressive symptoms after treatment with testosterone when compared with placebo. It was also noted that over administration of testosterone is associated with multiple adverse effects and complications.

CONCLUSION

The current evidence provides mixed conclusions on the effectiveness of testosterone therapy for treating depression. More research is needed in adult men to see if declining testosterone levels directly influence the development of depression.

The Implications of Mental Health and Trauma in Interstitial Cystitis

This review aims to assess the relationship between interstitial cystitis (IC) and significant traumatic events or PTSD. It was shown that there is a strong correlation between past trauma and the development of interstitial cystitis, as well as a much higher incidence of PTSD in patients diagnosed with IC. It was also established that for individuals with early traumatic experiences, the more likely the development of IC later in life, and with more severe symptoms and adverse effects on quality of life. We describe three distinct hypotheses for the possible physiologic mechanism for development of IC with relation to mental health and trauma, although definitive evidence in this area is still lacking, which poses interesting avenues for further research. This review also revealed an apparent lack of, and need for, trauma informed care and screening for PTSD in patients diagnosed with IC or other chronic pain syndromes.

Chaperones Utilization in Clinical Practice: Intimate and Sensitive Physical Examination Best Practice Strategies and Concepts in Modern Urological Medicine

The intention of utilizing chaperones during sensitive physical exams is to show respect to the patient, while simultaneously providing protection to both the patient and the medical provider. Despite clinical practice recommendations to offer chaperones for sensitive urologic exams, there is no data regarding the consistency of chaperone utilization. Our aim was to summarize the patient and provider perspectives on the role of chaperones in urology as well as identify barriers to implement chaperone consistency. In the present investigation, we conducted a systematic review of prospective, case-control, and retrospective studies and followed the PRISMA 2020 guidelines for data reporting. Studies were identified from PubMed, MEDLINE, and PMC using the Medical Subject Headings (MeSH) terms “chaperones, patient”, “chaperones, medical”, and keywords “chaperones”, and “urology”. Studies were included if they addressed patient/provider perspectives on chaperone utilization in urology specifically and were excluded if they investigated perspectives on chaperone utilization in other specialties. Preliminary study identification yielded 702 studies, 9 of which were eligible for this review after applying the inclusion and exclusion criteria. Of these, 4 studies focused on the patient perspective and 5 focused on the provider perspective. The percentage of patients that did not have a chaperone present during their urologic exam ranged from 52.9-88.5%. A greater proportion of these patients were male. Patients (59%) prefer a family member compared to a staff member as a chaperone. Physicians (60%) prefer staff member chaperones compared to family members. One study reported that 25.6% of patients did not feel comfortable to ask for a chaperone if they were not offered one. Two studies reported the percentage of patients who believed chaperones should be offered to all urology patients, ranging from 73-88.4%. Three studies reported the use of chaperones in the clinic which ranged from 5-72.5%. Two studies reported chaperone utilization documentation, ranging between 16-21.3%. Two studies reported the likelihood of chaperone utilization depending on gender of the physician, showing that male physicians were more likely to utilize chaperones and were 3x more likely to offer chaperones to their patients compared to female physicians. Research suggests that there are differing perspectives between patients and physicians regarding the specific role and benefits chaperones offer during a sensitive urologic examination, as well as differences in preferences of who should perform the role of the chaperone. While more work needs to be done to bridge the divide between clinical practice and patient/physician preferences, the act of offering chaperones to urologic patients, regardless if they want to utilize a chaperone for their examination is respectful of patient privacy and decision making.

Racial Disparities and Mental Health Effects Within Prostate Cancer

Disparities in prostate cancer (PCa) exist at all stages: screening, diagnosis, treatment, outcomes, and mortality. Although there are a multitude of complex biological (e.g., genetics, age at diagnosis, PSA levels, Gleason score) and nonbiological (e.g., socioeconomic status, education level, health literacy) factors that contribute to PCa disparities, nonbiological factors may play a more significant role. One understudied aspect influencing PCa patients is mental health related to the quality of life. Overall, PCa patients report poorer mental health than non-PCa patients and have a higher incidence of depression and anxiety. Racial disparities in mental health, specifically in PCa patients, and how poor mental health impacts overall PCa outcomes require further study.

Dhat Syndrome: Epidemiology, Risk Factors, Comorbidities, Diagnosis, Treatment, and Management

Dhat syndrome is a culture-bound psychiatric syndrome most commonly found in the Indian subcontinent. It has been characterized as the experiential fear of losing semen through ejaculation, nocturnal emission, or other means. While Dhat syndrome is common in the Indian subcontinent, given the lack of representativeness, generalizability, and closer connection to Ayurvedic system, there have been limited studies or recognition of symptoms among healthcare providers around the world. In this review, we describe Dhat syndrome, its epidemiology, risk factors, comorbidities, diagnosis, treatment, and its management. For patients with Dhat syndrome, it becomes important to appreciate how generalized depression and anxiety may persist alongside the disorder and those symptoms can be common and non-specific. Related to its strong cultural connection with South Asia such as the belief on Dhat's role in health and vitality influence, it also becomes important to recognize that the syndrome can be found in other populations and the importance of cultural humility and nonconfrontational approach for patient care. In summary, this review provides an informative understanding of Dhat syndrome for non-Indian clinicians who may not be prepared for a patient encounter with vague somatic symptoms in the context of semen loss. Treatment for Dhat syndrome is the same as treatments for major depressive disorder.

Rare Mental Health Disorders Affecting Urologic Care: A Comprehensive Review

Management of mental health illnesses and needs are important in fostering psychosocial support, interprofessional coordination, and greater adherence to treatment protocols in the field of urology. This can be especially true for mental health conditions that may greatly impact the presentation of a patient in the healthcare setting with urologic symptoms. This review describes the history, epidemiology, pathophysiology, clinical presentation, and treatment of somatic symptom disorder, illness anxiety disorder, compulsive sexual behavior/hypersexuality, factitious disorder, malingering symptoms, and conversion disorder in the realm of urology. Given the newly updated psychiatric diagnoses in the Diagnostic and Statistical Manual of Mental Disorders, fifth edition, there has been a lack of studies reviewing how these illnesses may present in a urology patient encounter. Additionally, as these mental health illnesses may carry a rare incidence compared to other well-known mental health illness such as generalized depression or generalized anxiety disorder, we have found that the lack of provisions and recognition of the diseases can prolong the timeline for diagnosis and lead to an increased cost in both healthcare and quality of life of patients with these mental health illnesses. This review provides awareness on these mental health conditions which may greatly impact patient history and presentation within the field of urology. Additionally, urologic care providers may have an improved understanding of interdisciplinary management of such illnesses and the common symptoms patients may present with such diseases.

Opioids in Urology: How Well Are We Preventing Opioid Dependence and How Can We Do Better?

Urologic procedures (both open and minimally invasive) can cause pain due to the surgery itself, devices placed, and post-operative issues. Thus, pain management is important for every post-procedure recovery period. Opioid use post-surgery is common and often over-prescribed contributing to persistent use by patients. In this article, we review the extent of opioid use in pediatric urologic procedures, vasectomy, endourologic procedures, penile implantation, urogynecologic procedures, prostatectomy, nephrectomy, cystectomy, and scrotal/testicular cancer surgery. Generally, we have found that institutions do not have a standardized protocol with a set regimen to prescribe opioids, resulting in more opioids being prescribed than needed and patients not properly disposing of their unused prescriptions. However, many institutions recognize their opioid overuse and are implementing new multimodal opioid-sparing analgesics methods such as non-opioid peri-operative medications, minimally invasive robotic surgery, and nerve blocks or local anesthetics with varying degrees of success. By shedding light on these opioid-free methods and prescription protocols, along with improved patient education and counselling, we hope to bring awareness to institutions and decrease unnecessary opioid use.

Ketamine-Induced Cystitis: A Comprehensive Review of the Urologic Effects of This Psychoactive Drug

Ketamine is a common medical anesthetic and analgesic but is becoming more widely used as a recreational drug. Significant side effects on the urinary tract are associated with frequent recreational ketamine use most notably ketamine-induced cystitis (KIC). Regular ketamine consumption has been shown to increase the risk of cystitis symptoms by 3- to 4-fold, and cessation of ketamine use is usually associated with improvement of symptoms. Common KIC-related problems are urinary pain and discomfort, bladder epithelial barrier damage, reduced bladder storage and increased pressure, ureter stenosis, and kidney failure, all of which significantly impact patients' quality of life. Furthermore, it becomes a vicious cycle when KIC patients attempt to manage their urinary pain with increased ketamine use. The precise pathophysiology of KIC is still unknown but several theories exist, most of which highlight the inflammatory signaling pathways leading to bladder epithelium damage due to presence of ketamine in the urine. Empirical treatment options for KIC are available and consist of ketamine cessation, noninvasive therapies, and surgery, and should be decided upon based on the time course and severity of the disease. Of note, cessation of use is strongly recommended for all KIC patients, and should be supplemented with motivational interviews and psychological and social support. It is crucial for clinicians to be familiar with KIC diagnosis and treatment, and to be prepared to have informed discussions with ketamine-using patients about the potential health consequences of ketamine.

Vasectomy Regret or Lack Thereof

Background

Vasectomy is a procedure that results in permanent yet reversible sterility and remains a great contraceptive option for many. Previous research studies have highlighted frequency of vasectomy utilization, defining characteristics of individuals who opt for this method, various surgical techniques, and the risks and benefits associated with the procedure. What remains to be defined is why or why not individuals may experience post-vasectomy regret and whether the previous characteristics correlate.

Objective

The objective of this review is to synthesize information regarding reasons individuals may regret their vasectomy and seek reversal, what options exist for accomplishing the reversal, and patients' fertility prognosis post-vasovasostomy.

Methods

This review utilized a combination of secondary and tertiary data analysis across a wide scope of academic databases pertaining to the topic of interest.

Results

Typically, most males who have sought a vasectomy are satisfied with their decision, however, approximately 6% of this population seeks reversal. Key factors influencing vasectomy regret include age at the time of vasectomy, parental status, pre- and post-operative relationship status, unresolved physical and psychosexual problems, and development of chronic scrotal pain following the procedure. Few options exist for vasectomy reversal including microsurgical reconstructive vasectomy reversal (VR) and sperm extraction for in vitro fertilization. There is no guarantee that fertility will be restored in any case but a major predictive factor for success is the time interval prior to reversal.

Conclusion

Vasectomy is intended to be a permanent form of contraception; however, a minor chance remains that individuals may experience post-operative regret due to various factors. This warrants proper comprehensive counseling by the patient's provider regarding benefits and risks, procedural outcomes, opportunities for reversal, and fertility prognosis.

Protocol of trans-Tasman feasibility randomised controlled trial of the Younger Women's Wellness After Breast Cancer (YWWACP) lifestyle intervention

BACKGROUND

Younger women (defined as those < 50 years who are likely pre-menopausal at time of diagnosis) with breast cancer often experience persistent treatment-related side effects that adversely affect their physical and psychological wellbeing. The Women's Wellness After Cancer Program (WWACP) was adapted and piloted in Australia to address these outcomes in younger women. The aims of this feasibility study are to determine (1) the potential to translate the Younger WWACP (YWWACP) intervention to a broader population base in Aotearoa/New Zealand and Australia, and (2) the potential for success of a larger, international, phase ΙΙΙ, randomised controlled trial.

METHODS

This bi-national, randomised, single-blinded controlled trial involves two main study sites in Aotearoa/New Zealand (Kōwhai study) and Australia (EMERALD study). Young women aged 18 to 50 years who completed intensive treatment (surgery, chemotherapy, and/or radiotherapy) for breast cancer in the previous 24 months are eligible. The potential to translate the YWWACP to women in these two populations will be assessed according to several feasibility outcomes. These include examining intervention accessibility, acceptability and uptake; intervention sustainability and adherence; the prevalence components of the intervention in the control group; intervention efficacy; participants' perception of measurement burden; the effectiveness of planned recruitment strategies; and trial methods and procedures. The studies collectively aim to enrol 60 participants in the intervention group and 60 participants in the control group (total = 120 participants).

DISCUSSION

Ethical approval has been received from the Southern Health and Disability Ethics Committee (Kōwhai ref: 19/STH/215), and UnitingCare Human Research Ethics Committee (EMERALD ref: 202103). This study will provide important data on the feasibility of the refined YWWACP in the trans-Tasman context. This study will account for and harmonise cross-country differences to ensure the success of a proposed international grant application for a phase ΙΙΙ randomised controlled trial of this program to improve outcomes in younger women living with breast cancer.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR): Kōwhai ACTRN12620000260921 , registered on 27 February 2020. EMERALD ACTRN12621000447853 , registered on 19 April 2021.

Second Case of Tumors Associated With Heterozygous NTHL1 Variant

Homozygous mutations to NTHL1 are known to increase cancer risk, particularly in the colon and breast. NTHL1 tumor syndrome (NTS) is an autosomal recessive genetic condition. Little is known about the cancer risk in patients who have heterozygous NTHL1 mutations. We previously published a case of benign tumors associated with a heterozygous NTHL1 mutation. In this second case, we present a patient with a heterozygous NTHL1 mutation who developed a gastrointestinal stromal tumor, pilocytic astrocytoma, tall cell papillary thyroid cancer, invasive ductal papilloma, spinal nerve sheath tumors, and spinal hemangiomas. Here, we show that heterozygous NTHL1 mutations may increase cancer risk and may even manifest similarly to NTS.

Temporary standalone percutaneous fixation with pedicle screws for the treatment of subacute tuberculous osteomyelitis with kyphotic deformity in the lumbar spine

Background:

Tuberculous (TB) osteomyelitis is a rare, but challenging infection, that mandates antituberculosis antibiotics, and potentially surgical intervention. Per the Gulhane Askeri Tip Akademisi (GATA) classification system, corrective reconstruction is indicated in severe cases, where the kyphotic deformity is >20° (GATA Class III). Here, we describe a case of BCG vaccine-induced lumbar TB osteomyelitis at the L1-2 level in a patient presenting with mechanical pain and a focal, nonfixed kyphotic deformity of 36.1°. Surgery consisted of percutaneous fixation with pedicle screws without debridement, fusion arthrodesis, or anterior reconstruction.

Case Description:

A 77-year-old male presented with L1-2 TB osteomyelitis secondary to intravesical BCG application. A 36.1° focal nonfixed kyphotic deformity was evident on standing X-rays that reduced in the supine position. He underwent posterior percutaneous screw fixation with rods extending from the T12 to L3 levels, with resolution of his mechanical pain. Nine months later, the CT demonstrated reconstitution of the vertebral bodies (i.e., volume increase of 6.99 cm³ (21%) and 7.49 cm³ (27%) at L1 and L2, respectively). Standing X-rays after hardware removal demonstrated 32.7° of lumbar lordosis and a reduction of focal kyphosis to 12.9°.

Conclusion:

Here, we present an exceedingly rare case of BCG vaccine-induced L1-2 spinal tuberculosis with extensive vertebral body destruction and deformity. This was effectively treated with standalone temporary pedicle fixation instead of corpectomy and reconstruction.

Vulvar Leiomyosarcoma Masquerading as a Bartholin’s Gland Cyst in an Adolescent

Sarcomas, tumors of mesenchymal origin, comprise a small percentage of all malignant tumors and are often challenging to diagnose. Leiomyosarcoma (LMS) is a rare form of cancer arising from smooth muscle cells. While a soft tissue sarcoma diagnosis is rare in and of itself, LMS diagnosis at an adolescent age is even more unique. Vulvar LMS can easily be misdiagnosed as a benign vaginal lesion, leading to a delay in proper treatment and poorer outcomes. In this case, we present a 14-year-old female who was diagnosed with a grade 2 vulvar LMS that clinically mimicked a Bartholin’s gland cyst.

A Network of Anomalies Prompting VACTERL Workup in a Trisomy 21 Newborn

VACTERL (vertebral defects, anal atresia, cardiac defects, tracheoesophageal fistula, renal anomalies, and limb abnormalities) association is a condition defined by having at least three of the following congenital malformations: vertebral defects, anal atresia, cardiac defects, tracheoesophageal fistula, renal anomalies, and limb abnormalities. While diagnosing the VACTERL association is rare, the conditions that make up the VACTERL core-component features among other congenital abnormalities are even more unique. We present a case of a 34-week-old premature infant with trisomy 21 in addition to esophageal atresia, tracheoesophageal fistula, laryngeal cleft, vascular ring, Hirschsprung’s disease, atrioventricular canal defect, ventricular septal defect, and other related conditions diagnosed at birth. To our knowledge, this case represents the first of its kind in relation to the constellation of anomalies diagnosed in one individual at birth of which may or may not be related to Down syndrome, and the associated interventions necessary to continue postnatal living.

Placenta Percreta Complications

Placenta percreta is the most severe form of placenta accreta and is characterized by placental invasion through the entirety of the myometrium and possibly into extrauterine tissues. It is associated with prior cesarean deliveries and placenta previa. Herein, we present the case of a patient who developed placenta percreta and experienced massive blood loss of 27 liters. She developed many complications over the next 11 months, including deep vein thrombosis, pulmonary embolism, preeclampsia after pregnancy, hematoma, blood clots in the bladder, lactation failure, ileus, vesicovaginal fistula, excessive scar tissue requiring surgery, loss of an ovary, and recurrent bladder perforation. We analyze the mechanisms of these complications and the most common complications associated with placenta percreta.

Cocaine and Levamisole Induced Vasculitis

Levamisole adulterated cocaine is a rare cause of anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis. It is increasingly diagnosed because of raised awareness; however, it is still underdiagnosed in part because of its rarity and patients not reporting cocaine use. Here we report a case of levamisole-induced vasculitis. We present a 48-year-old non-Hispanic white male with a past medical history significant for Crohn’s Disease and pneumonia who presented with acute bilateral ear pain and rash. His urinary drug screen was positive, which prompted suspicion of contamination and potential levamisole adulterated cocaine-associated vasculitis. A punch biopsy showed evidence of leukocytoclastic vasculitis and multiple fibrin thrombi further supporting contamination with levamisole. We believe this case highlights the importance of using patient history in guiding diagnostic testing in the setting of acute vasculitis. Once the history of illicit substance use was confirmed, our differential diagnosis and considerations for treatment significantly changed. 

Retrohepatic Mass: A Case of Human Herpesvirus-8 Negative Multicentric Castleman's Disease

Multicentric Castleman's disease (MCD) is a rare lymphoproliferative disorder with aggressive systemic presentation and poor prognosis. Here, we present a case of MCD in a 37-year-old Asian American woman with a past medical history of the polycystic ovarian syndrome (PCOS), human papilloma virus (HPV), herpes simplex virus-1 (HSV-1), iron deficiency, and vitamin B₁₂ deficiency-related anemia. The patient underwent surgical resection with good recovery. Hemoglobin and erythrocyte sedimentation rate (ESR) normalized after surgical resection. Although the influence of risk factors such as human immunodeficiency virus (HIV) or human herpesvirus-8 (HHV-8) infections on MCD relapse are not well understood, patient education on MCD risk factors is important, as they may place the patient at greater risk for recurrence. MCD should be considered in patients with chronic inflammation and a mass on imaging.

Staple Line Erosion in a Neobladder Causing Postoperative Hematuria

Erosion of metal surgical staples is a rare but described surgical complication. Staple erosion in a bladder may present with hematuria, urinary tract infection (UTI), bladder pain, or fistula. We present a 64-year-old male with a history of urothelial carcinoma treated by cystoprostatectomy with neobladder reconstruction. Over the next two to three years, he developed hematuria and had multiple urine cytologies suspicious for cancer. The cystoscopic evaluation revealed staple line erosion but no cancer. We believe this to be the first published case of symptomatic staple erosion in a neobladder. Clinicians should be aware that staple line erosion in a neobladder can occur and mimic malignancy recurrence.

Benign Tumors Associated With Heterozygous NTHL1 Variant

NTHL1 is a tumor suppressor gene involved in base excision repair. It is associated with an increased risk for colorectal and breast cancer when two variant gene copies are inherited. However, inheriting one variant NTHL1 copy is not associated with increased tumor risk. Genetic counselors report heterozygous NTHL1 mutations as benign. We present the case of a 22-year-old patient with a heterozygous NTHL1 variant who developed an arm schwannoma, spinal schwannoma, and hepatic hemangioma. The patient also reported feeling multiple other bumps on his body but did not seek medical care due to a lack of symptoms. This case suggests that heterozygous NTHL1 variants may be implicated in tumor development.

Charcot Spinal Arthropathy-Induced Progression From Upper to Lower Motor Neuron Bowel Syndrome

Charcot spinal arthropathy is a progressively degenerative joint disorder of the vertebrae. Historically, it was a common consequence of tertiary syphilis. Currently, it is a rare complication of spinal cord injury (SCI). We present the case of a 28-year-old patient with paraplegia who developed progressive, neurogenic bowel dysfunction due to Charcot spinal arthropathy. Our patient had upper motor neuron bowel syndrome secondary to SCI which advanced to lower motor neuron bowel syndrome. Charcot spinal arthropathy should be considered as a possible cause for symptom progression in SCI patients. This case illustrates the connection between Charcot spine and lower motor neuron dysfunction in the setting of prior upper motor neuron dysfunction.

Liquid biopsy for cancer diagnosis using vibrational spectroscopy: systematic review

Background

Vibrational spectroscopy (VS) is a minimally invasive tool for analysing biological material to detect disease. This study aimed to review its application to human blood for cancer diagnosis.

Methods

A systematic review was undertaken using a keyword electronic database search (MEDLINE, Embase, PubMed, TRIP and Cochrane Library), with all original English‐language manuscripts examining the use of vibrational spectral analysis of human blood for cancer detection. Studies involving fewer than 75 patients in the cancer or control group, animal studies, or where the primary analyte was not blood were excluded.

Results

From 1446 results, six studies (published in 2010–2018) examining brain, bladder, oral, breast, oesophageal and hepatic cancer met the criteria for inclusion, with a total population of 2392 (1316 cancer, 1076 control; 1476 men, 916 women). For cancer detection, reported mean sensitivities in each included study ranged from 79·3 to 98 per cent, with specificities of 82·8–95 per cent and accuracies between 81·1 and 97·1 per cent. Heterogeneity in reporting strategies, methods and outcome measures made meta‐analysis inappropriate.

Conclusion

VS shows high potential for cancer diagnosis, but until there is agreement on uniform standard reporting methods and studies with adequate sample size for valid classification models have been performed, its value in clinical practice will remain uncertain.

Vaginal lactic acid elicits an anti-inflammatory response from human cervicovaginal epithelial cells and inhibits production of pro-inflammatory mediators associated with HIV acquisition

Inflammation in the female reproductive tract (FRT) is associated with increased HIV transmission. Lactobacillus spp. dominate the vaginal microbiota of many women and their presence is associated with reduced HIV acquisition. Here we demonstrate that lactic acid (LA), a major organic acid metabolite produced by lactobacilli, mediates anti-inflammatory effects on human cervicovaginal epithelial cells. Treatment of human vaginal and cervical epithelial cell lines with LA (pH 3.9) elicited significant increases in the production of the anti-inflammatory cytokine IL-1RA. When added simultaneously or prior to stimulation, LA inhibited the Toll-like receptor agonist-elicited production of inflammatory mediators IL-6, IL-8, TNFα, RANTES, and MIP3α from epithelial cell lines and prevented IL-6 and IL-8 production by seminal plasma. The anti-inflammatory effect of LA was mediated by the protonated form present at pH≤3.86 and was observed with both L- and D-isomers. A similar anti-inflammatory effect of LA was observed in primary cervicovaginal cells and in an organotypic epithelial tissue model. These findings identify a novel property of LA that acts directly on epithelial cells to inhibit FRT inflammation and highlights the potential use of LA-containing agents in the lower FRT as adjuncts to female-initiated strategies to reduce HIV acquisition.

Potent and selective small-molecule MCL-1 inhibitors demonstrate on-target cancer cell killing activity as single agents and in combination with ABT-263 (navitoclax)

The anti-apoptotic protein MCL-1 is a key regulator of cancer cell survival and a known resistance factor for small-molecule BCL-2 family inhibitors such as ABT-263 (navitoclax), making it an attractive therapeutic target. However, directly inhibiting this target requires the disruption of high-affinity protein-protein interactions, and therefore designing small molecules potent enough to inhibit MCL-1 in cells has proven extremely challenging. Here, we describe a series of indole-2-carboxylic acids, exemplified by the compound A-1210477, that bind to MCL-1 selectively and with sufficient affinity to disrupt MCL-1-BIM complexes in living cells. A-1210477 induces the hallmarks of intrinsic apoptosis and demonstrates single agent killing of multiple myeloma and non-small cell lung cancer cell lines demonstrated to be MCL-1 dependent by BH3 profiling or siRNA rescue experiments. As predicted, A-1210477 synergizes with the BCL-2/BCL-XL inhibitor navitoclax to kill a variety of cancer cell lines. This work represents the first description of small-molecule MCL-1 inhibitors with sufficient potency to induce clear on-target cellular activity. It also demonstrates the utility of these molecules as chemical tools for dissecting the basic biology of MCL-1 and the promise of small-molecule MCL-1 inhibitors as potential therapeutics for the treatment of cancer.

Inhibition of αvβ6 promotes acute renal allograft rejection in nonhuman primates

The integrin αvβ6 activates latent transforming growth factor-β (TGF-β) within the kidney and may be a target for the prevention of chronic allograft fibrosis after kidney transplantation. However, TGF-β also has known immunosuppressive properties that are exploited by calcineurin inhibitors (CNIs); thus, the net benefit of αvβ6 inhibition remains undetermined. To assess the acute impact of interference with αvβ6 on acute rejection, we tested a humanized αvβ6-specific monoclonal antibody (STX-100) in a randomized, double-blinded, placebo-controlled nonhuman primate renal transplantation study to evaluate whether αvβ6 blockade alters the risk of acute rejection during CNI-based immunosuppression. Rhesus monkeys underwent renal allotransplantation under standard CNI-based maintenance immunosuppression; 10 biopsy-confirmed rejection-free animals were randomized to receive weekly STX-100 or placebo. Animals treated with STX-100 experienced significantly decreased rejection-free survival compared to placebo animals (p = 0.049). Immunohistochemical analysis confirmed αvβ6 ligand presence, and αvβ6 staining intensity was lower in STX-100-treated animals (p = 0.055), indicating an apparent blockade effect of STX-100. LAP, LTBP-1 and TGF-β were all decreased in animals that rejected on STX-100 compared to those that rejected on standard immunosuppression alone, suggesting a relevant effect of αvβ6 blockade on local TGF-β. These data caution against the use of αvβ6 blockade to achieve TGF-β inhibition in kidney transplantation.

Belatacept and sirolimus prolong nonhuman primate renal allograft survival without a requirement for memory T cell depletion

Belatacept is an inhibitor of CD28/B7 costimulation that is clinically indicated as a calcineurin inhibitor (CNI) alternative in combination with mycophenolate mofetil and steroids after renal transplantation. We sought to develop a clinically translatable, nonlymphocyte depleting, belatacept-based regimen that could obviate the need for both CNIs and steroids. Thus, based on murine data showing synergy between costimulation blockade and mTOR inhibition, we studied rhesus monkeys undergoing MHC-mismatched renal allotransplants treated with belatacept and the mTOR inhibitor, sirolimus. To extend prior work on costimulation blockade-resistant rejection, some animals also received CD2 blockade with alefacept (LFA3-Ig). Belatacept and sirolimus therapy successfully prevented rejection in all animals. Tolerance was not induced, as animals rejected after withdrawal of therapy. The regimen did not deplete T cells. Alefecept did not add a survival benefit to the optimized belatacept and sirolimus regimen, despite causing an intended depletion of memory T cells, and caused a marked reduction in regulatory T cells. Furthermore, alefacept-treated animals had a significantly increased incidence of CMV reactivation, suggesting that this combination overly compromised protective immunity. These data support belatacept and sirolimus as a clinically translatable, nondepleting, CNI-free, steroid-sparing immunomodulatory regimen that promotes sustained rejection-free allograft survival after renal transplantation.

Direct visualization of Bcl-2 family protein interactions using live cell fluorescent protein redistribution assays

Bcl-2 family proteins have important roles in tumor initiation, progression and resistance to therapy. Pro-survival Bcl-2 proteins are regulated by their interactions with pro-death BH3-only proteins making these protein–protein interactions attractive therapeutic targets. Although these interactions have been extensively characterized biochemically, there is a paucity of tools to assess these interactions in cells. Here, we address this limitation by developing quantitative, high throughput microscopy assays to characterize Bcl-2 and BH3-only protein interactions in live cells. We use fluorescent proteins to label the interacting proteins of interest, enabling visualization and quantification of their mitochondria-localized interactions. Using tool compounds, we demonstrate the suitability of our assays to characterize the cellular activity of putative therapeutic molecules that target the interaction between pro-survival Bcl-2 and pro-death BH3-only proteins. In addition to the relevance of our assays for drug discovery, we anticipate that our work will contribute to an improved understanding of the mechanisms that regulate these important protein–protein interactions within the cell.

Spatial steering of deep brain stimulation volumes using a novel lead design

OBJECTIVE

To investigate steering the volume of activated tissue (VTA) with deep brain stimulation (DBS) using a novel high spatial-resolution lead design.

METHODS

We examined the effect of asymmetric current-injection across the DBS-array on the VTA. These predictions were then evaluated acutely in a non-human primate implanted with the DBS-array, using motor side-effect thresholds as the metric for estimating VTA asymmetries.

RESULTS

Simulations show the DBS-array, with electrodes arranged together in a cylindrical configuration, can generate field distributions equivalent to commercial DBS leads, and these field distributions can be modulated using field-steering methods. Stimulation with implanted DBS-arrays showed directionally-selective muscle activation, presumably through spread of stimulation fields into portions of the corticospinal tract lying in the internal capsule.

CONCLUSIONS

Our computational and experimental studies demonstrate that the DBS-array is capable of spatially selective stimulation. Displacing VTAs away from the lead's axis can be achieved using a single simple and intuitive control parameter.

SIGNIFICANCE

Optimal DBS likely requires non-uniform VTAs that may differentially affect a nucleus or fiber pathway. The DBS-array allows positioning VTAs with sub-millimeter precision, which is especially relevant for those patients with DBS leads placed in sub-optimal locations. This may present clinicians with an additional degree of freedom to optimize the DBS therapy.

Seasonal peaks in Escherichia coli infections: possible explanations and implications

Escherichia coli is a common cause of infections in all populations and countries of the world, causing an enormous burden of disease. In this issue of Clinical Microbiology and Infection, Al-Hasan et al. describe seasonal peaks in the incidence of E. coli bloodstream infection (BSI) during the summer for a population of 125 000 in Minnesota, USA. We discuss the probability that similar seasonal peaks in the incidence of E. coli BSI occur in other populations and geographical regions. Second, we discuss possible underlying explanations for these findings in terms of seasonal changes in human behaviour and the effect of temperature on the ability of E. coli to survive in the environment. Finally, we discuss some of the possible implications of E. coli BSI being a seasonal illness. More specifically, we discuss how better understanding the reasons for seasonality may potentially help us to better understand the dominant routes by which human populations are exposed to clonal groups of E. coli associated with urinary tract infection.

Comparative phylogeography of brown (Sula leucogaster) and red-footed boobies (S. sula): the influence of physical barriers and habitat preference on gene flow in pelagic seabirds

To test the hypothesis that both physical and ecological barriers to gene flow drive population differentiation in tropical seabirds, we surveyed mitochondrial control region variation in 242 brown boobies (Sula leucogaster), which prefer inshore habitat, and 271 red-footed boobies (S. sula), which prefer pelagic habitat. To determine the relative influence of isolation and gene flow on population structure, we used both traditional methods and a recently developed statistical method based on coalescent theory and Bayesian inference (Isolation with Migration). We found that global population genetic structure was high in both species, and that female-mediated gene flow among ocean basins apparently has been restricted by major physical barriers including the Isthmus of Panama, and the periodic emergence of the Sunda and Sahul Shelves in Southeast Asia. In contrast, the evolutionary history of populations within ocean basins differed markedly between the two species. In brown boobies, we found high levels of population genetic differentiation and limited gene flow among colonies, even at spatial scales as small as 500km. Although red-footed booby colonies were also genetically differentiated within ocean basins, coalescent analyses indicated that populations have either diverged in the face of ongoing gene flow, or diverged without gene flow but recently made secondary contact. Regardless, gene flow among red-footed booby populations was higher than among brown booby populations. We suggest that these contrasting patterns of gene flow within ocean basins may be explained by the different habitat preferences of brown and red-footed boobies.

Pharmacology of alpha7 nicotinic acetylcholine receptor mediated extracellular signal-regulated kinase signalling in PC12 cells

BACKGROUND AND PURPOSE

Neuronal nicotinic acetylcholine receptors (nAChR) can modulate cell survival and memory processing. The involvement of specific nAChR subtypes in downstream signalling events has been ill defined thus far, because of a lack of subtype-selective ligands. In this study, we investigated activation and modulation of alpha7 nAChR-mediated phosphorylation of extracellular signal-regulated kinases (ERK1/2) in PC12 cells, using selective agonists and positive allosteric modulators.

EXPERIMENTAL APPROACH

We used undifferentiated PC12 cells endogenously expressing alpha7 nAChR for both biochemical and functional studies. ERK phosphorylation changes were measured by using a novel In-Cell Western procedure. alpha7 nAChR-mediated Ca(2+) signalling was determined by using the fluorometric imaging plate reader assay.

KEY RESULTS

Robust induction of ERK phosphorylation followed exposure of PC12 cells to the selective agonist PNU-282987 in the presence of the alpha7 nAChR modulator PNU-120596. ERK phosphorylation was transient and was attenuated by the selective antagonist methyllycaconitine. Consistent with allosteric modulation of alpha7 nAChRs, PNU-120596 enhanced both the agonist potency and efficacy in activating ERK. Moreover, alpha7 nAChR agonists could be quantitatively differentiated based on their potency in activating ERK signalling. The rank order of potencies correlated fairly well with the corresponding binding K(i) values of these alpha7 nAChR agonists.

CONCLUSIONS AND IMPLICATIONS

The present work extends previous observations demonstrating the involvement of alpha7 nAChRs in ERK1/2 phosphorylation in PC12 cells. The In-Cell Western procedure allowed a detailed investigation of alpha7 nAChR function and downstream ERK signalling in response to agonist and allosteric modulators.

Cutaneous sensory neurons expressing the Mrgprd receptor sense extracellular ATP and are putative nociceptors

Sensory neurons expressing the Mrgprd receptor are known to innervate the outermost living layer of the epidermis, the stratum granulosum. The sensory modality that these neurons signal and the stimulus that they respond to are not established, although immunocytochemical data suggest they could be nonpeptidergic nociceptors. Using patch clamp of dissociated mouse dorsal root ganglion (DRG) neurons, the present study demonstrates that Mrgprd+ neurons have several properties typical of nociceptors: long-duration action potentials, TTX-resistant Na(+) current, and Ca(2+) currents that are inhibited by mu opioids. Remarkably, Mrgprd+ neurons respond almost exclusively to extracellular ATP with currents similar to homomeric P2X3 receptors. They show little or no sensitivity to other putative nociceptive agonists, including capsaicin, cinnamaldehyde, menthol, pH 6.0, or glutamate. These properties, together with selective innervation of the stratum granulosum, indicate that Mrgprd+ neurons are nociceptors in the outer epidermis and may respond indirectly to external stimuli by detecting ATP release in the skin.

alpha7 nicotinic acetylcholine receptor agonist properties of tilorone and related tricyclic analogues

BACKGROUND AND PURPOSE

The alpha7 nicotinic acetylcholine receptor (nAChR) has attracted considerable interest as a target for cognitive enhancement in schizophrenia and Alzheimer's Disease. However, most recently described alpha7 agonists are derived from the quinuclidine structural class. Alternatively, the present study identifies tilorone as a novel alpha7-selective agonist and characterizes analogues developed from this lead.

EXPERIMENTAL APPROACH

Activity and selectivity were determined from rat brain alpha7 and alpha4beta2 nAChR binding, recombinant nAChR activation, and native alpha7 nAChR mediated stimulation of ERK1/2 phosphorylation in PC12 cells.

KEY RESULTS

Tilorone bound alpha7 nAChR (IC(50) 110 nM) with high selectivity relative to alpha4beta2 (IC(50) 70 000 nM), activated human alpha7 nAChR with an EC(50) value of 2.5 microM and maximal response of 67% relative to acetylcholine, and showed little agonist effect at human alpha3beta4 or alpha4beta2 nAChRs. However, the rat alpha7 nAChR maximal response was only 34%. Lead optimization led to 2-(5-methyl-hexahydro-pyrrolo[3,4-c]pyrrol-2-yl)-xanthen-9-one (A-844606) with improved binding (alpha7 IC(50) 11 nM, alpha4beta2 IC(50)>30 000 nM) and activity at both human and rat alpha7 nAChR (EC(50)s 1.4 and 2.2 microM and apparent efficacies 61 and 63%, respectively). These compounds also activated native alpha7 nAChR, stimulating ERK1/2 phosphorylation in PC12 cells.

CONCLUSIONS AND IMPLICATIONS

Tilorone, known as an interferon inducer, is a selective alpha7 nAChR agonist, suggesting utility of the fluorenone pharmacophore for the development of alpha7 nAChR selective agonists. Whether alpha7 stimulation mediates interferon induction, or whether interferon induction may influence the potential anti-inflammatory properties of alpha7 nAChR agonists remains to be elucidated.

Progesterone receptor expression by human leukocyte cell lines: molecular mechanisms of cytokine suppression

PURPOSE

We investigated progesterone (P) signaling in human leukemia cells, shown to downregulate cytokines with P.

METHODS

The following tests were utilized: PCR with FAM labeled primers and Gene Scan with the Applied Biosystems 373 DNA sequencer for progesterone receptor (PR) mRNA, immunohistochemistry using monoclonal antibodies (Zymed and Ventana) for PR protein, RT-PCR for glucocorticoid receptor (GR), NFkappaB (p65, p50, p52), c-rel, IkappaB-alpha, c-jun, c-fos, mRNA, transient transfections with pNF-kappaB-SEAP, and pGRE-SEAP vectors with chemiluminescence detection for NFkappaB and GR activity.

RESULTS

PR transcripts were demonstrated in MOT, U937, K562, THP-1, 8226, U226, not in JUKAT, HL60, HUT102, isolated normal peripheral blood mononuclear cells, or purified CD4+ or CD8+ T cells. Estradiol increased PR mRNA in MOT and U937. MOT, U937, K562, KG-1, 8226, ATL, and CD8+HTLV-1 expressed PR protein. SRIH-BATL, 729PH6NEO, HS-1, R-CLL, and JURKAT were negative. Steady state mRNA for GR, NFkappaB (p65, p50, p52), IkappaB-alpha, c-jun were unchanged with P in MOT and U937; c-fos and c-rel were not detected. There was a concentration-dependent reduction of NFkappaB activity with P in MOT and U937.

CONCLUSION

The mechanism of cytokine suppression by P is mediated at least in part by suppression of NFkappaB, but the interaction of sex hormones, receptors, and transcription factors is complex.

A SERS-Active System Based on Silver Nanoparticles Tethered to a Deposited Silver Film

A series of SERS-active nanostructures were produced by exposing a freshly deposited silver film (fabricated to be as free from roughness as practicable) to a solution containing a mixture of 1-decanethiol (m) and 1,9-nonanedithiol (d) of varying concentrations of m to d, then allowing colloidal silver nanoparticles to interact with the surface. Silver nanoparticles were found to bind exclusively to films which were prepared from solutions with a nonzero concentration of the dithiol implying that the nanoparticles were tethered to the silver surface by the dithiol with one of the thiolate groups bound to the nanoparticle and the other to the silver film. Intense SERS spectra were observed even from samples in which the m/d concentration ratio was so large that the adsorbed molecules in the vicinity of only approximately 8 +/- 3 nanoparticles were illuminated by the diffraction-limited focused laser beam. At such high dilution, the molecules (numbering at most approximately 330) residing in the SERS "hot spots" associated with the approximately 8 nanoparticles consisted primarily of m (although, of course, for each nanoparticle, at least one molecule in the hot spot had to be d to serve as the linker). This was corroborated by the SERS spectra. An analysis is presented, which accounts for the fact that as the concentration ratio of m/d increases, the SERS intensity associated with bands belonging to m first increases to a maximum then decreases. The nanoparticle-metal film system presented here is a simple embodiment of a more general range of SERS-active sensing platforms in which a molecular tether is used to create a SERS hot spot that (although nanosized) is large enough to accommodate analyte molecules that cannot themselves function as linkers, which are subsequently detected by SERS at the few-molecule level.

Enterococcal prosthetic valve infective endocarditis: report of 45 episodes from the International Collaboration on Endocarditis-merged database

Enterococcal prosthetic valve infective endocarditis (PVE) is an incompletely understood disease. In the present study, patients with enterococcal PVE were compared to patients with enterococcal native valve endocarditis (NVE) and other types of PVE to determine differences in basic clinical characteristics and outcomes using a large multicenter, international database of patients with definite endocarditis. Forty-five of 159 (29%) cases of definite enterococcal endocarditis were PVE. Patients with enterococcal PVE were demographically similar to patients with enterococcal NVE but had more intracardiac abscesses (20% vs. 6%; p=0.009), fewer valve vegetations (51% vs. 79%; p<0.001), and fewer cases of new valvular regurgitation (12% vs. 45%; p=0.01). Patients with either enterococcal PVE or NVE were elderly (median age, 73 vs. 69; p=0.06). Rates of in-hospital mortality, surgical intervention, heart failure, peripheral embolization, and stroke were similar in both groups. Patients with enterococcal PVE were also demographically similar to patients with other types of PVE, but mortality may be lower (14% vs. 26%; p=0.08). Notably, 93% of patients with enterococcal PVE came from European centers, as compared with only 79% of patients with enterococcal NVE (p=0.03). Thus, patients with enterococcal PVE have higher rates of myocardial abscess formation and lower rates of new regurgitation compared to patients with enterococcal NVE, but there are no differences between the groups with regard to surgical or mortality rates. In contrast, though patients with enterococcal PVE and patients with other types of PVE share similar characteristics, mortality is higher in the latter group. Importantly, the prevalence of enterococcal PVE was higher in the European centers in this study.

The Isthmus of Panama: a major physical barrier to gene flow in a highly mobile pantropical seabird

To further test the hypothesis that the Isthmus of Panama is a major barrier to gene flow in pantropical seabirds, we applied phylogeographic methods to mitochondrial control sequence variation in masked booby (Sula dactylatra) populations on either side of the Isthmus of Panama and the southern tip of Africa. In accord with Steeves et al. (2003), we found that all Caribbean masked boobies with the 'secondary contact' cytochrome b haplotype (m-B) shared a control region haplotype (Sd_100), which grouped with Indian-Pacific haplotypes and not Caribbean-Atlantic haplotypes. In addition, Sd_100 was more closely related to control region haplotypes in the Indian Ocean than in the Pacific. We also found that the 'secondary contact' birds diverged more recently from extant populations in the Indian Ocean than in the Pacific. Thus, it appears that these masked boobies did not breach the Isthmus of Panama. Rather, birds likely dispersed around the southern tip of Africa during favourable oceanographic conditions in the Pleistocene.