Inefficient tissue immune response against MPXV in an immunocompromised mpox patient.

The recent outbreak of monkeypox virus (MPXV) was unprecedented in its size and distribution. Those living with uncontrolled HIV and low CD4 T cell counts might develop a fulminant clinical mpox course with increased mortality, secondary infections, and necrotizing lesions. Fatal cases display a high and widespread MPXV tissue burden. The underlying pathomechanisms are not fully understood. We report here the pathological findings of an MPXV-driven abscess in gastrocnemius muscle requiring surgery in an immunocompromised patient with severe mpox. Presence of virus particles and infectivity were confirmed by electron microscopy, expansion microscopy, and virus culture, respectively. MPXV tissue distribution by immunohistochemistry (IHC) showed a necrotic core with infection of different cell types. In contrast, at the lesion rim fibroblasts were mainly infected. Immune cells were almost absent in the necrotic core, but were abundant at the infection rim and predominantly macrophages. Further, we detected high amounts of alternatively activated GPNMB+-macrophages at the lesion border. Of note, macrophages only rarely colocalized with virus-infected cells. Insufficient clearance of infected cells and infection of lesion-associated fibroblasts sustained by the abundance of profibrotic macrophages might lead to the coalescing of lesions and the severe and persistent clinical mpox course observed in immunocompromised patients.

Fatal outcome of SARS-CoV-2 infection (B1.1.7) in a 4-year-old child.

This case report highlights details of a case of critical acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) with B1.1.7 variant in a 4-year-old girl who died due to pneumonia and pulmonary hemorrhage. The girl was referred to our University ECMO Center from another University hospital for veno-arterial extracorporeal membrane oxygenation (VA-ECMO). In the clinical course, superinfection with Pseudomonas aeruginosa was detected. Virological evidence of herpes simplex sepsis was also obtained in blood samples on her day of death. Transcription polymerase chain reaction (PCR) confirmed SARS-CoV-2 infection in lung tissue. Postmortem computed tomography showed pulmonary hemorrhage with inhomogeneous density values in both lungs. Lung tissue showed no ventilated areas. Autopsy revealed a massively congested lung with evidence of acute respiratory distress syndrome (ARDS) and pneumonia with multiple abscesses. Histopathology showed a mixture of diffuse alveolar injury with hyaline membranes, massive hemorrhage, and bronchopneumonia with multiple granulocytic abscesses. Cardiac examination revealed pericarditis. Suspicion of myocarditis or myocardial infarction could not be confirmed microscopically. To our knowledge, this is the first autopsy-based case report of the death of a previously healthy child due to the new variant B 1.1.7 in Germany.

A case report and epidemiological investigation of axillary lymph node abscess caused by Corynebacterium ulcerans in an HIV-1-positive patient.

A human immunodeficiency virus-1 (HIV-1)-positive male undergoing antiretroviral therapy was diagnosed with an axillary lymph node abscess caused by Corynebacterium ulcerans, and an environmental survey revealed that the patient's cat as the source of infection.

Mast cells in Canine parvovirus-2-associated enteritis with crypt abscess.

The role of mast cells (MCs) in allergic reactions and parasitic infections is well established. Their involvement in host immune response against bacterial and viral infections is reported. In this study, investigation is made to determine if MCs are associated with Canine parvovirus-2 (CPV-2)-induced enteritis with crypt abscess (ECA). Mast cell count (MCC) was made on toluidine blue-stained intestinal sections from a total of 34 dogs. These included 16 dogs exhibiting ECA positive for CPV-2 and negative for Canine distemper virus and Canine coronavirus by immunohistochemistry and fluorescent antibody test, 12 dogs with inflammatory bowel disease (IBD), and 6 non-ECA/non-IBD (control) dogs. The average total MCC per high-power field in ECA (40.8 ± 2.2) and IBD (24.7 ± 2.1) was significantly higher (P < .05) than in the control (3.4 ± 0.6). Although not significant (P > .05), MCC was also higher in ECA than in IBD. The present study for the first time has documented significantly increased MCs in CPV-2-associated ECA as was previously reported for IBD, showing that MCs may also play an important role in CPV-2-associated ECA. Further studies involving more CPV-infected dogs are recommended to substantiate the findings.

Case Report: Iliopsoas Hematoma during the Clinical Course of Severe COVID-19 in Two Male Patients.

Anticoagulation plays a major role in reducing the risk of systematic thrombosis in patients with severe COVID-19. Serious hemorrhagic complications, such as intracranial hemorrhage, have also been recognized. However, intra-abdominal hemorrhage is under-recognized because of its rare occurrence, despite high mortality. Here, we discuss two cases of spontaneous iliopsoas hematoma (IPH) likely caused by anticoagulants during the clinical course of COVID-19. We also explored published case reports to identify clinical characteristics of IPH in COVID-19 patients. The use of anticoagulants may increase the risk of lethal IPH among COVID-19 patients becsuse of scarce data on optimal dosage and adequate monitoring of anticoagulant effects. Rapid diagnosis and timely intervention are crucial to ensure good patient outcomes.

Seroprevalences of feline leukemia virus and feline immunodeficiency virus in cats with abscesses or bite wounds and rate of veterinarian compliance with current guidelines for retrovirus testing.

OBJECTIVE: To determine the seroprevalences of and seroconversion rates for FeLV and FIV infection in cats treated for bite wounds and cutaneous abscesses and to evaluate compliance with recommendations to determine the retrovirus infection status of cats at acquisition and 60 days after a high-risk event. DESIGN: Prospective study. ANIMALS: 967 cats from 134 veterinary practices in 30 states. PROCEDURES: Cats with bite wounds or abscesses were evaluated by use of a point-of-care immunoassay for blood-borne FeLV antigen and FIV antibody. Veterinarians were asked to retest cats approximately 60 days later to determine whether seronegative cats had seroconverted after injury. RESULTS: The combined FeLV-FIV status of only 96 (9.9%) cats was known prior to wound treatment. At the time of treatment, 187 (19.3%) cats were seropositive for 1 or both viruses. Age (adult), sex (male), history of cutaneous wounds, and outdoor access were significantly associated with seropositivity. At 73 of 134 (54.5%) veterinary practices, retesting of cats for retrovirus infection status was recommended to owners of 478 cats. Only 64 (13.4%) cats were retested; of these, 3 of 58 (5.2%) cats that were initially seronegative for FIV antibody seroconverted. CONCLUSIONS AND CLINICAL RELEVANCE: A high proportion of cats with abscesses or bite wounds were seropositive for FeLV antigen or FIV antibody. Compliance with recommendations to test cats for retrovirus infection status at acquisition or after treatment for injury was low. The FeLV-FIV infection status of cats with potential fight wounds should be determined at time of treatment and again 60 days later.

Non-cutaneous AIDS-associated Kaposi's sarcoma presenting as recurrent rectal abscesses.

Kaposi's sarcoma is a fatal disease that typically presents with cutaneous manifestations in immunocompromised individuals. There are a small number of documented cases where patients diagnosed with this disease present without cutaneous lesions. We present a 35-year-old man with recurrent rectal abscesses and fistula-in-ano, which required multiple drainage procedures. Further investigation revealed a diagnosis of HIV-AIDS, and biopsy of a rectal mass confirmed the diagnosis of visceral Kaposi's sarcoma, despite the absence of cutaneous involvement. Workup revealed hepatic metastasis and a second pulmonary primary malignancy. The patient denied chemotherapy or further intervention and was subsequently lost to follow-up. Prompt diagnosis of Kaposi's sarcoma and initiation of treatment is vital to decrease disease progression. A high index of suspicion should be present in immunocompromised patients, and clinicians must recognise atypical presentations in order to improve long-term survival.

Absceso frío estafilocócico en un neonato / Staphylococcal cold abscess in a neonate

El absceso frío estafilocócico neonatal es una patología infecciosa localizada que ocurre en periodo neonatal con evolución benigna y de la cual hay pocas referencias en la bibliografía. Se presenta un caso para dar a conocer esta patología (AU)

Neonatal staphylococcal cold abscess refers to a local manifestation of infectious disease that occurs in the neonatal period and has favourable outcomes, on which there is currently a dearth of evidence. We present one case to contribute to the knowledge of this pathology. (AU)

Characterization of Bovine herpesvirus type 4 isolated from cattle with mastitis and subclinical infection by the virus among cattle.

An outbreak of contagious mastitis occurred among cattle on a farm, and bovine herpesviruses were isolated from the affected mammary tissues, scabs and abscess discharge of the cattle. A bovine herpesvirus type 4 (BoHV-4)-specific fragment was amplified from the isolates by polymerase chain reaction (PCR). Restriction endonuclease analyses demonstrated that the isolates were related to Movar-like European type BoHV-4. To determine the ratio of BoHV-4 subclinical infection in the cattle, a genomic survey was performed by PCR for cattle that were moved to the animal hygiene service station in Ibaraki prefecture. The BoHV-4 genome was occasionally detected in peripheral blood leukocytes, lymph nodes and nervous tissues. The rate of BoHV-4 subclinical infection was relatively high in the cattle.

Molluscum contagiosum--a novel presentation.

A case history is described of an HIV-seropositive man who presented with a swelling on the right cheek and a history of disseminated molluscum contagiosum. Electron microscopy of the abscess aspirate showed pox virions indicative of molluscum contagiosum. This is an unusual presentation of molluscum contagiosum and the authors review the literature of other presentations.

[Infective stomatitis of the palate]. / Localización palatina de las estomatitis infecciosas.

Having on base a wide and selective review of the literature, it has seemed to us interesting to detail the infective pathology on this location or sometimes occurring. This region is, as well will see, the seat of a rich pathology. We pretend on the other hand to reassess the importance of the meticulous examination of the oral cavity in "systemic problems". We describe the palatal infections divided in four groups: bacterial, viral, fungal and parasitory, according to the causal agent. We review the palatine manifestations of other fewer current syndromes as well.

Dynamics of breast milk HIV-1 RNA with unilateral mastitis or abscess.

BACKGROUND: Mastitis and abscess in HIV-infected women increase the risk of breastfeeding transmission of HIV. Guidelines encourage women to stop breastfeeding on the affected breast and feed on the contralateral breast. However, impact of breast pathology on breast milk HIV dynamics is unknown. METHODS: HIV RNA was quantified in 211 breast milk samples collected before, during, and after a clinical mastitis or an abscess diagnosis from 38 HIV-infected women participating in a Zambian breastfeeding study. HIV RNA quantity was compared between affected and unaffected breasts over time using generalized estimating equation models. A sample of 115 women without breast pathology was selected as a control group. RESULTS: In the affected breast, breast milk HIV RNA quantity increased from the pre- to during-pathology period by log(10) 0.45 copies per milliliter [95% confidence interval (CI): 0.16 to 0.74], and after symptom resolution, HIV RNA levels were no different from prepathology levels (log10 -0.04 copies per milliliter 95% CI: -0.33 to 0.25). In the contralateral, unaffected breast, HIV RNA quantity did not significantly increase (log(10) 0.15 copies per milliliter, 95% CI: -0.41 to 0.10). Increase was more marked in women with abscess or with a greater number of mastitis symptoms. HIV RNA was not significantly different between affected and unaffected women, except at the time of diagnosis. CONCLUSIONS: Breast milk HIV RNA increased modestly in the affected breast with unilateral mastitis or abscess and returned to prepathology levels with symptom resolution. Contralateral HIV RNA was not affected. Results support guidelines encouraging feeding from the contralateral breast to minimize the risk of HIV transmission associated with unilateral breast pathology.

Experimental bacteriophage protection against Staphylococcus aureus abscesses in a rabbit model.

In a rabbit model of wound infection caused by Staphylococcus aureus, 2 x 10(9) PFU of staphylococcal phage prevented abscess formation in rabbits when it was injected simultaneously with S. aureus (8 x 10(7) CFU) into the same subcutaneous site. Phage multiplied in the tissues. Phages might be a valuable prophylaxis against staphylococcal infection.

The significance of microabscesses in liver transplant biopsies: a clinicopathological study.

Parenchymal microabscesses (MA) in liver transplant biopsies are frequently associated with cytomegalovirus (CMV) infection. However, other potential causes of MA have not been fully investigated. We studied additional etiologies for MA via histological evaluation and clinicopathological correlation. Three hundred seventy-two liver transplant biopsies from 97 patients (from 1991 to 1997) were reviewed and stained immunohistochemically for CMV. Numerous histological features were evaluated including size and number of MA, lobular and portal inflammation, and cholestasis. Medical records were reviewed for radiographic, laboratory, and other clinical data from the time of biopsy. The chi2 or Fisher's Exact test and ANOVA with adjusted multiple comparisons were used to determine statistical significance. Sixty-two of 372 biopsies (17%) from 43 patients contained MA. Biopsies were obtained between 4 days and 2.3 years posttransplant (median, 14 days). Nineteen percent of biopsies had CMV infection at the time of biopsy; 27% were associated with other bacterial, viral, or fungal infections; 10% had graft ischemia; 15% had biliary obstruction/cholangitis; 3% had a combination of ischemia and sepsis; and no explanation was found in 26% of biopsies. Numerous MA within a biopsy (>9) correlated with CMV infection (P <.005); no other histological features, including size of MA, correlated with the etiology of MA. Overall, 43 of 97 (44%) liver transplantation patients at our institution had biopsies demonstrating MA at some point in their posttransplantation course. CMV infection appears responsible for only a minority of cases. MA, although nonspecific, are an important histological finding in numerous conditions that may have a significant impact on both graft survival and overall patient morbidity.