Review of Laser Treatments for Post-Inflammatory Hyperpigmentation in Skin of Color.

Post-inflammatory hyperpigmentation is an extremely common disorder of pigmentation in skin of color. It most frequently and severely affects phototypes that are rich in melanin and often has a chronic and unpredictable course. It presents significant treatment challenges and often requires a multi-factorial approach. We review the literature available for the optimal use of laser-based devices in the treatment of post-inflammatory hyperpigmentation, particularly for Fitzpatrick skin phototypes III-VI. For the treatment of post-inflammatory hyperpigmentation in skin of color, lasers remain second line to topical agents based on the variable response, cost, and risk of complications with laser use. For post-inflammatory hyperpigmentation resistant to topicals, laser devices, particularly neodymium:yttrium-aluminum-garnet and fractional photothermolysis systems, can provide adjunctive treatment in skin of color patients when appropriate parameters are used. Future studies would benefit from an objective and consistent assessment to assist with a systematic analysis.

Imported Monkeypox from International Traveler, Maryland, USA, 2021.

A case of monkeypox was diagnosed in a returning traveler from Nigeria to Maryland, USA. Prompt infection control measures led to no secondary cases in 40 exposed healthcare workers. Given the global health implications, public health systems should be aware of effective strategies to mitigate the potential spread of monkeypox.

A retrospective review of cutaneous lymphoma in Botswana.

BACKGROUND: Primary cutaneous lymphoma (PCL) represents a heterogeneous collection of non-Hodgkin lymphomas originating in the skin. Our study describes the clinical and histological findings of cutaneous lymphoma within Botswana to expand the paucity of data on this rare disease in sub-Saharan Africa. METHODS: We conducted a retrospective review from the dermatology clinic at Princess Marina Hospital (Gaborone, Botswana) of patients evaluated by skin biopsy for cutaneous lymphoma between 2008 and 2017. Patients with initial diagnostic suspicion for cutaneous lymphoma had biopsies re-reviewed by experienced dermatopathologists and were given a final diagnosis of either (i) cutaneous lymphoma, (ii) atypical lymphocytic infiltrate (ALI), or (iii) a reactive cutaneous process. RESULTS: Thirty-eight cases were identified with a mean age of 50.0 years and a male:female (M:F) ratio of 13:6. Final diagnoses included: 27 cases of cutaneous lymphoma, eight cases of ALI, and three cases of reactive cutaneous processes. Subtypes of cutaneous lymphoma diagnosed included: mycosis fungoides (MF) (81.5%), plasmablastic lymphoma (7.4%), Epstein-Barr virus-positive T-cell lymphoma (3.7%), subcutaneous panniculitis-like T-cell lymphoma (3.7%), and peripheral T-cell lymphoma, not otherwise specified (3.7%). The most common immunohistochemical staining profile in MF cases was CD8 predominance over CD4. CONCLUSIONS: Primary cutaneous lymphoma causes significant morbidity and mortality globally. Given the limited resources in sub-Saharan Africa, it is essential to educate providers on the manifestations and histology of PCL. This study is an important step towards understanding the demographics, clinical presentation, histologic features, and mortality of patients diagnosed with PCL in Botswana and similar low-resource settings.

HIV-associated erythema elevatum diutinum: a case report and review of a clinically distinct variant.

A 24-year-old man with untreated human immunodeficiency virus (HIV) infection consulted our outreach clinic owing to the development of numerous asymptomatic nodules on his palms and fingers. Histopathologic evaluation revealed leukocytoclastic vasculitis and prominent fibrosis with a neutrophilic infiltrate consistent with erythema elevatum diutinum (EED). We referred the patient for initiation of antiretroviral therapy and started him on dapsone. The pathogenesis of EED is not completely understood, but it has been associated with numerous systemic conditions that may be infectious, inflammatory, or neoplastic. Only recently has EED been recognized as a defined reactive dermatosis of HIV. We present an exemplary case of HIV-associated EED and review the differential diagnosis, highlighting clinical features of EED that appear to be more frequently encountered in the HIV-infected population.

Genomic Surveillance Reveals Diversity of Multidrug-Resistant Organism Colonization and Infection: A Prospective Cohort Study in Liver Transplant Recipients.

Background: Multidrug-resistant organisms (MDROs) are an important cause of morbidity and mortality after solid organ transplantation. We aimed to characterize MDRO colonization dynamics and infection in liver transplant (LT) recipients through innovative use of active surveillance and whole-genome sequencing (WGS). Methods: We prospectively enrolled consecutive adult patients undergoing LT from March 2014 to March 2016. Fecal samples were collected at multiple timepoints from time of enrollment to 12 months posttransplant. Samples were screened for carbapenem-resistant Enterobacteriaceae (CRE), Enterobacteriaceae resistant to third-generation cephalosporins (Ceph-RE), and vancomycin-resistant enterococci. We performed WGS of CRE and selected Ceph-RE isolates. We also collected clinical data including demographics, transplant characteristics, and infection data. Results: We collected 998 stool samples and 119 rectal swabs from 128 patients. MDRO colonization was detected in 86 (67%) patients at least once and was significantly associated with subsequent MDRO infection (0 vs 19.8%, P = .002). Child-Turcotte-Pugh score at LT and duration of post-LT hospitalization were independent predictors of both MDRO colonization and infection. Temporal dynamics differed between MDROs with respect to onset of colonization, clearance, and infections. We detected an unexpected diversity of CRE colonizing isolates and previously unrecognized transmission that spanned Ceph-RE and CRE phenotypes, as well as a cluster of mcr-1-producing isolates. Conclusions: Active surveillance and WGS showed that MDRO colonization is a highly dynamic and complex process after LT. Understanding that complexity is crucial for informing decisions regarding MDRO infection control, use of therapeutic decolonization, and empiric treatment regimens.

Successful management of congenital/infantile fibrosarcoma presenting as large, non-healing buttock ulceration.

A two-year-old boy presented with a large, non-healing ulceration on his left buttock, which was originally noted as a brown patch present at birth. Punch skin biopsy was performed and histopathology revealed an atypical, pleomorphic, spindled proliferation in whorled fascicles replacing the dermis and trapping fat in the subcutis, consistent with a diagnosis of congenital/infantile fibrosarcoma. No evidence of metastatic spread was seen on imaging. The tumor was initially deemed unresectable owing to extent of local invasion. Neo-adjuvant chemotherapy caused significant tumor shrinkage and the patient underwent complete resection.

The Surface Protein SdrF Mediates Staphylococcus epidermidis Adherence to Keratin.

Background: Staphylococcus epidermidis, a major component of skin flora, is an opportunist, often causing prosthetic device infections. A family of structurally related proteins mediates staphylococcal attachment to host tissues, contributing to the success of S. epidermidis as a pathogen. We examined the ability of the surface protein SdrF to adhere to keratin, a major molecule expressed on the skin surface. Methods: A heterologous Lactococcus lactis expression system was used to express SdrF and its ligand-binding domains. Adherence to keratin types 1 and 10, human foreskin keratinocytes, and nasal epithelial cells was examined. Results: SdrF bound human keratins 1 and 10 and adhered to keratinocytes and epithelial cells. Binding involved both the A and B domains. Anti-SdrF antibodies reduced adherence of S. epidermidis to keratin and keratinocytes. RNA interference reduced keratin synthesis in keratinocytes and, as a result, SdrF adherence. Direct force measurements using atomic force microscopy showed that SdrF mediates bacterial adhesion to keratin 10 through strong and weak bonds involving the A and B regions; strong adhesion was primarily mediated by the A region. Conclusions: These studies demonstrate that SdrF mediates adherence to human keratin and suggest that SdrF may facilitate S. epidermidis colonization of the skin.

Human cytomegalovirus miR-UL112-1 promotes the down-regulation of viral immediate early-gene expression during latency to prevent T-cell recognition of latently infected cells.

Human cytomegalovirus, a member of the herpesvirus family, can cause significant morbidity and mortality in immune compromised patients resulting from either primary lytic infection or reactivation from latency. Latent infection is associated with a restricted viral transcription programme compared to lytic infection which consists of defined protein coding RNAs but also includes a number of virally encoded microRNAs (miRNAs). One of these, miR-UL112-1, is known to target the major lytic IE72 transcript but, to date, a functional role for miR-UL112-1 during latent infection has not been shown. To address this, we have analysed latent infection in myeloid cells using a virus in which the target site for miR-UL112-1 in the 3' UTR of IE72 was removed such that any IE72 RNA present during latent infection would no longer be subject to regulation by miR-UL112-1 through the RNAi pathway. Our data show that removal of the miR-UL112-1 target site in IE72 results in increased levels of IE72 RNA in experimentally latent primary monocytes. Furthermore, this resulted in induction of immediate early (IE) gene expression that is detectable by IE-specific cytotoxic T-cells (CTLs); no such CTL recognition of monocytes latently infected with wild-type virus was observed. We also recapitulated these findings in the more tractable THP-1 cell line model of latency. These observations argue that an important role for miR-UL112-1 during latency is to ensure tight control of lytic viral immediate early (IE) gene expression thereby preventing recognition of latently infected cells by the host's potent pre-existing anti-viral CTL response.

Population Structure of Klebsiella pneumoniae Causing Bloodstream Infections at a New York City Tertiary Care Hospital: Diversification of Multidrug-Resistant Isolates.

Despite the growing importance of carbapenem-resistant Klebsiella pneumoniae (CRKP), the clonal relationships between CRKP and antibiotic-susceptible isolates remain unclear. We compared the genetic diversity and clinical features of CRKP, third-generation and/or fourth-generation cephalosporin-resistant (Ceph-R) K. pneumoniae, and susceptible K. pneumoniae isolates causing bloodstream infections at a tertiary care hospital in New York City between January 2012 and July 2013. Drug susceptibilities were determined with the Vitek 2 system. Isolates underwent multilocus sequence typing and PCR sequencing of the wzi and blaKPC genes. Clinical and microbiological data were extracted from patient records and correlated with molecular data. Among 223 patients, we identified 272 isolates. Of these, 194 were susceptible, 30 Ceph-R, and 48 CRKP, belonging to 144 sequence types (STs). Susceptible (127 STs) and Ceph-R (20 STs) isolates were highly diverse. ST258 dominated CRKP strains (12 STs, with 63% ST258). There was minimal overlap in STs between resistance groups. The blaKPC-3 gene (30%) was restricted to ST258/wzi154, whereas blaKPC-2 (70%) was observed for several wzi allele types. CRKP infections occurred more frequently among solid organ transplant (31%) and dialysis (17%) patients. Mortality rates were high overall (28%) and highest among CRKP-infected patients (59%). In multivariable analyses, advanced age, comorbidities, and disease severity were significant predictors of 30-day mortality rates, whereas the K. pneumoniae susceptibility phenotype was not. Among CRKP infections, we observed a borderline significant association of increased mortality rates with ST258 and the wzi154 allele. Although the clonal spread of ST258 continues to contribute substantially to the dissemination of CRKP, non-ST258 strains appear to be evolving. Further investigations into the mechanisms promoting CRKP diversification and the effects of clonal backgrounds on outcomes are warranted.

Community-associated methicillin-resistant Staphylococcus aureus case studies.

Over the past decade, the emergence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has changed the landscape of S. aureus infections around the globe. Initially recognized for its ability to cause disease in young and healthy individuals without healthcare exposures as well as for its distinct genotype and phenotype, this original description no longer fully encompasses the diversity of CA-MRSA as it continues to expand its niche. Using four case studies, we highlight a wide range of the clinical presentations and challenges of CA-MRSA. Based on these cases we further explore the globally polygenetic background of CA-MRSA with a special emphasis on generally less characterized populations.

Emergence of sequence type 398 as a community- and healthcare-associated methicillin-susceptible staphylococcus aureus in northern Manhattan.

The methicillin-susceptible Staphylococcus aureus (MSSA) clone sequence type (ST) 398 has increasingly been identified as a pathogen in diverse geographic settings, yet its epidemiology remains incompletely understood. In this case-control study of MSSA infections, we identified ST398 MSSA as both a major community- and hospital-associated MSSA pathogen in the Dominican neighborhood of northern Manhattan.