Rethinking interleukin-6 blockade for treatment of COVID-19.

Interleukin-6 (IL-6) is a pleiotropic cytokine with effects in immune regulation, inflammation, and infection. The use of drugs that inhibit IL-6 biological activity has been proposed as a treatment for patients with Coronavirus Disease 2019 (COVID-19). The rationale for this approach includes commitment to the concept that inflammation is a cause of lung damage in COVID-19 and belief that IL-6 is a pro-inflammatory molecule. Observational data thought to support IL-6 inhibition include elevated circulating IL-6 levels in COVID-19 patients and association between elevated IL-6 and poor clinical outcomes. However, IL-6 has significant anti-inflammatory properties, which calls into question the rationale for employing IL-6 blockade to suppress inflammation-induced tissue injury. Also, studies suggesting a beneficial role for IL-6 in the host response to infection challenge the strategy of using IL-6 blockade to treat COVID-19. In studies of recombinant IL-6 injected into human volunteers, IL-6 levels exceeding those measured in COVID-19 patients have been observed with no pulmonary adverse events or other organ damage. These observations question the role of IL-6 as a contributing factor in COVID-19. Clinical experience with IL-6 receptor antagonists such as tocilizumab demonstrates increase in severe and opportunistic infections, raising concern about using tocilizumab and similar agents to treat COVID-19. Trials of drugs to inhibit IL-6 activity in COVID-19 are ongoing and will shed light on the role of IL-6 in COVID-19 pathogenesis. However, until more information is available, providers should exercise caution in prescribing these therapies given the potential for patient harm.

Case Report: Cutaneous Leishmaniasis due to Leishmania (Viannia) panamensis in Two Travelers Successfully Treated with Miltefosine.

We present two cases of Leishmania (V) panamensis in returning travelers from Central America successfully treated with miltefosine. The couple presented with ulcerative skin lesions nonresponsive to antibiotics. Skin biopsy with polymerase chain reaction (PCR) revealed L. (V) panamensis. To prevent the development of mucosal disease and avoid the inconvenience of parental therapy, we treated both patients with oral miltefosine. We suggest that miltefosine represents an important therapeutic alternative in the treatment of cutaneous lesions caused by L. panamensis and in preventing mucosal involvement.

Cutaneous Manifestations of Mycobacterium kansasii Infection.

Purpose of Review: Mycobacterium kansasii is a slow-growing member of the nontuberculous mycobacterial species that manifests clinically with pulmonary, cutaneous, or disseminated forms. Most cases of M. kansasii infection occur in immunocompromised hosts including HIV/AIDS, solid-organ transplantation, anti-interferon-γ antibody disorder, or among those with pulmonary disorders such as chronic obstructive pulmonary disease or cystic fibrosis. In this review, we aim to discuss relevant literature regarding the clinical manifestations of this infection with a particular emphasis on the clinical spectrum and treatment of the cutaneous manifestations of this mycobacterial infection. Recent Findings: Infection caused by M. kansasii is associated with exposure to contaminated municipal water systems since this organism thrives in human-engineered environments. Chronic or subacute skin lesions may represent the primary source of entry of the organism due to open sores or traumatic injuries. Alternatively, cutaneous lesions may occur secondary to dissemination of the organism to the skin from pulmonary infection. The diagnosis of M. kansasii of the skin and soft tissues should be entertained among immunocompetent or immunocompromised individuals presenting with subacute or chronic lesions. The differential diagnosis of M. kansasii infection includes infections of skin and soft tissues caused by rapidly growing mycobacteria, subcutaneous mycosis, pyogenic bacterial infections, nocardiosis, free-living amoebas, and protothecosis. Summary: Cutaneous lesions caused by M. kansasii most commonly manifest in the setting of concomitant pulmonary disease or in the setting of disseminated infection among immunocompromised hosts. When clinicians suspect a cutaneous mycobacterial infection either due to slow-growing mycobacteria such as M. kansasii or due to rapidly growing mycobacteria, obtaining a skin biopsy of chronic nonhealing lesions for histopathologic evaluation and for microbiological assessment is crucial. Mycobacteriology assessment of clinical specimen includes acid-fast bacilli staining, culture in solid/liquid media, and molecular assays for confirmation. Treatment of M. kansasii infection of the skin and subcutaneous tissues follows the same management recommendations as those for the treatment of isolated pulmonary forms or disseminated disease.

Congenital and Neonatal Chikungunya in Colombia.

In Latin America and the Caribbean (LAC), chikungunya (CHIK) viral infection has emerged as a significant arboviral disease. This rapidly expanding vector-borne viral illness is associated with a substantial burden of disease in terms of acute illness and also in terms of long-term sequelae. In addition, this viral pathogen has the ability to impact different populations including pregnant women and newborns. Despite the growing threat of this arboviral infection to the region, there are insufficient reports or studies attempting to delineate the clinical and epidemiological features of congenital and neonatal cases of CHIK in LAC. In this study, we present a case of congenital CHIK and a case of neonatal CHIK infection identified in Santander, Colombia. We discuss the potential neurological impact and sequelae of CHIK infection acquired during the neonatal period. There is an urgent need for further epidemiological and clinical studies to better understand the impact of CHIK in endemic areas in LAC.

A rare opportunistic infection in a woman with systemic lupus erythematosus and multiple skin lesions.

Cutaneous lesions in patients with systemic lupus erythematosus (SLE) represent diagnostic challenges. Opportunistic infections should be considered when lupus patients are on immunosuppressive therapy and other causes, such as disease activity, are less likely to explain the skin lesions. Within the spectrum of skin opportunistic infections that might occur in SLE patients, Blastomyces dermatitidis should be suspected when acid-fast positive material with no bacilliform organisms is seen on Ziehl-Nielsen skin biopsy preparations. In this study, we describe one patient with SLE on immunosuppressive therapy, who developed cutaneous blastomycosis despite living in a non-endemic area. Because of lack of awareness about this association and misinterpretation of the skin biopsy results, the diagnosis of atypical mycobacterial infection was initially considered. Subsequent proper tissue staining and interpretation revealed the correct diagnosis of disseminated cutaneous blastomycosis. This description represents the first report of this rare opportunistic skin infection in SLE, illustrating the importance of performing correct preparation and elucidation of the skin biopsy to avoid misdiagnosis and treatment delay.

Hematogenous osteomyelitis mimicking osteosarcoma due to Community Associated Methicillin-Resistant Staphylococcus aureus.

Community Associated Methicillin-Resistant Staphylococcus aureus (CA-MRSA) is an emerging pathogen with increasing clinical significance. Initially recognized as a cause of skin and soft tissue infections, it has soon been shown to cause life threatening illnesses. We describe two cases of osteomyelitis of the femur in young otherwise healthy adults. Initially a preliminary diagnosis of osteosarcoma was suggested by radiologic studies and both patients underwent an excisional biopsy. Following identification of the pathogen as CA-MRSA (Panton-Valentine leukocidin positive USA300 clone), both patients were successfully treated with prolonged courses of vancomycin.

[Immunogenicity and safety of the influenza vaccine, in a population older than 55-years in Mexico]. / Inmunogenicidad y tolerancia de una vacuna contra influenza, en una población mexicana mayor de 55 años de edad.

OBJECTIVE: To confirm the immunogenicity and tolerance of the inactivated, fractionated, and purified influenza vaccine, in a Mexican adult population aged 55 and older, medically served at a Petróleos Mexicanos Hospital (Pemex, Mexican Oil Company). MATERIAL AND METHODS: The study was conducted between November and December, 2000, among ninety adult subjects aged 55 years and older who were seen at the Hospital Central Sur Pemex. The primary endpoints regarding immunogenicity were the percentage of individuals with protective antibodies targeting hemagglutinins higher than or equal to 1:40, and the percentage of subjects who seroconverted as measured by a four-fold increase in protective antibody production. Secondary endpoints included the frequency of local and systemic reactions to the vaccine. An additional criterion that was evaluated included antigen-antibody affinity assays to measure the polyclonal antibody response to the vaccine and the specific generation of high-affinity antibodies to viral proteins, before and after vaccination. RESULTS: The antibody protection rate was 95.6% against the HINI strain, 98.9% against the H3N2 strain, and a 100% against the B/Yamanashi strain. Seroconversion to the HINI strain was elicited in 74.4% of subjects, to the H3N2 strain in 88.9%, and to the B/Yamanashi strain in 82.2%. Eighteen (20%) subjects developed local reactions; 17 (18.8%) developed a systemic reaction post vaccination at day 5 and nine subjects (10%) at day 28. Local reactions consisted of pain in 10 (11.1%) subjects, redness in 8 (8.8%), and induration in 6 (6.6%). General malaise, headache, and fever were identified in 10, 8.8, and 0% of subjects, respectively, at day 5, and in 4.4, 6.6, and 0%, respectively, at day 28. CONCLUSIONS: Influenza vaccine was highly immunogenic in a healthy Mexican adult population aged 55 years and older. The generation of high-affinity antibodies to the virus after vaccination was also demonstrated. Local and systemic adverse reactions to the vaccine identified in our study were similar to those in previous reports. The results of this study can be extrapolated to other health institutions serving this adult population to increase influenza vaccine coverage rates.

Psoas muscle abscess caused by Mycobacterium tuberculosis and Staphylococcus aureus: case report and review.

Tuberculosis psoas muscle abscess is currently an uncommon clinical entity in industrialized countries. It was considered the predominant cause of these abscesses in the early part of the 20th century as a result of complicated Potts disease. We describe the case of a psoas abscess caused by the combination of Mycobacterium tuberculosis and Staphylococcus aureus. In this patient, the abscess was not associated with Potts disease but with osteomyelitis of the iliac crest, in which the evaluation with magnetic resonance imaging was very specific in determining the extent and regional spread.