Figure 1 Purpuric rash of a leg with surrounding partially infiltrated rash areas. Figure 2 Purpuric rash of a knee.

Acting on the cytokine cascade is key to preventing disease progression and death in hospitalised patients with COVID-19. Among anti-cytokine therapies, interleukin (IL)-6 inhibitors have been the most used and studied since the beginning of the pandemic. Going through previous observational studies, subsequent randomised controlled trials, and meta-analyses, we focused on the baseline characteristics of the patients recruited, identifying the most favourable features in the light of positive or negative study outcomes; taking into account the biological significance and predictivity of IL-6 and other biomarkers according to specific thresholds, we ultimately attempted to delineate precise windows for therapeutic intervention. By stimulating scavenger macrophages and T-cell responsivity, IL-6 seems protective against viral replication during asymptomatic infection; still protective on early tissue damage by modulating the release of granzymes and lymphokines in mild-moderate disease; importantly pathogenic in severe disease by inducing the proinflammatory activation of immune and endothelial cells (through trans-signalling and trans-presentation); and again protective in critical disease by exerting homeostatic roles for tissue repair (through cis-signalling), while IL-1 still drives hyperinflammation. IL-6 inhibitors, particularly anti-IL-6R monoclonal antibodies (e.g., tocilizumab, sarilumab), are effective in severe disease, characterised by baseline IL-6 concentrations ranging from 35 to 90 ng/mL (reached in the circulation within 6 days of hospital admission), a ratio of partial pressure arterial oxygen (PaO2) and fraction of inspired oxygen (FiO2) between 100 and 200 mmHg, requirement of high-flow oxygen or non-invasive ventilation, C-reactive protein levels between 120 and 160 mg/L, ferritin levels between 800 and 1600 ng/mL, D-dimer levels between 750 and 3000 ng/mL, and lactate dehydrogenase levels between 350 and 500 U/L. Granulocyte-macrophage colony-stimulating factor inhibitors might have similar windows of opportunity but different age preferences compared to IL-6 inhibitors (over or under 70 years old, respectively). Janus kinase inhibitors (e.g., baricitinib) may also be effective in moderate disease, whereas IL-1 inhibitors (e.g., anakinra) may also be effective in critical disease. Correct use of biologics based on therapeutic windows is essential for successful outcomes and could inform future new trials with more appropriate recruiting criteria.

Background In COVID-19 patients the progressive clinical deterioration seems secondary to the activation of a cytokine storm. Ferritin is considered a direct mediator of the immune system and some evidences suggested a shared physio-pathogenic basis between COVID-19 and ‘Hyperferritinemic Syndromes.’ The aim of our study was to evaluate the prognostic role of ferritin in COVID-19 patients. Methods We retrospectively studied consecutive COVID-19 patients admitted to four Italian Internal Medicine Units. Role of potential prognostic markers was evaluated with binary logistic regression analysis and results were expressed as odds ratios (ORs) with the corresponding 95% confidence intervals (CIs). Poor outcome was defined as death or need to transfer in the intensive care unit. Results Two hundred patients were included (mean age 68.75 ± 13.22 years). Ferritin value was highly elevated (>3000 ng/mL) in 8% of our population; 13% of patients were transferred to intensive care units and 12% of patients died. At multivariate analysis, highly elevated ferritin levels (OR 16.67 C.I. 4.89–57.57 p < 0.001) and hemoglobin < 10 g/dL (OR 8.88 C.I. 2.02–39.09 p = 0.004) were independently associated with a bad outcome. Patients with ferritin values > 3000 ng/ml appeared to have an inflammatory activation with elevated values of CRP and D-dimer and low values of lymphocyte count. Conclusion Our results confirm the prognostic role of ferritin in hospitalized COVID-19 patients. Patients with high ferritin levels should be considered critically ill and treated in an adequate setting. Furthermore, COVID-19 seems to share some characteristics with hyperferritinemic syndromes with potential therapeutic implications.

Capillaroscopy is an actual inexpensive imaging technique, used to examine, non-invasively and safely, the morphology of nailfold dermal papillary capillaries. Many studies agree in the statement that the capillaroscopy is one of the gold standard methods for non-invasive examination of the microcirculation and it plays an important role in screening in Raynaud’s phenomenon and in monitoring of systemic sclerosis and other rheumatologic diseases. There are also many reports on the possible use of nailfold capillaroscopy in the diagnosis and monitoring of many other diseases in internal medicine.

Good’s syndrome (GS) or thymomaassociated immunodeficiency is a rare clinical entity that should be ruled out in patients with thymoma who develop severe, recurrent bacterial infections and opportunistic viral and fungal infections. There are no treatment protocols established, hence, early recognition is imperative to avoid complications. We report the case of a 42-year-old female, known for a previous thymectomy for giant thymoma who has suffered for a long time from recurrent pulmonary and urinary tract infections and cold sores. In March 2016 she referred to our unit complaining of fever, cough, chest pain, and cold sores due to Herpes simplex virus (HSV), confirmed serologically as HSV-1. Chest X-ray showed left pneumonia due to Streptococcus pneumoniae. She started antibiotics (amoxicillin/clavulanic acid associated with azithromycin) with gradual improvement. Given her history she was studied for an underlying immunodeficiency: IgG, IgA, and IgM were significantly low or absent, as well as all IgG subclasses; blood and bone marrow aspirate leucocyte immunophenotyping showed complete absence of B lymphocytes and reduced CD4+ T cells. In light of: i) thymoma; ii) B lymphocyte deficit; iii) hypogammaglobulinemia; iv) recurrent infections, GS was diagnosed and pre-emptive immunoglobulin treatment, associated with HSV and Pneumocystis jiroveci prophylaxis (Acyclovir for HSV and Sulfamethoxazole- Trimethoprim for P. jiroveci) were started. Since then the patient has no longer presented any infectious episodes.