Revista medica de Chile最新文献

Paroxysmal Nocturnal Hemoglobinuria (PNH) is a non-malignant clonal hematopoietic stem cell disorder characterized by intravascular and extravascular hemolysis, thrombosis, and potentially life-threatening systemic complications. Without treatment, the 5-year survival rate is approximately 50%. Advances in complement-inhibiting therapies have significantly improved the quality of life and survival of these patients.

Aim: To review the pathophysiology, clinical presentation, diagnosis, and current and emerging treatments for PNH, highlighting the benefits of complement-inhibiting drugs.

Methods: A literature review of the literature on the pathophysiology and treatments of PNH was conducted, covering studies from March 2010 to May 2024. The review included 42 articles from PUBMED/NCBI, of which 29 met the inclusion criteria and were selected for an in-depth analysis of pathophysiology, diagnosis, and therapeutic options.

Results: Flow cytometry is the diagnostic method of choice for identifying PNH clones. Patients with classical PNH treated with C5 inhibitors (eculizumab and ravulizumab) exhibit an overall survival rate exceeding 95% at 5 years, with significant reductions in hemolysis, thrombotic episodes, and transfusion dependency. However, persistent extravascular hemolysis remains a challenge affecting morbidity and mortality. New proximal complement pathway inhibitors, such as iptacopan, have demonstrated greater efficacy in controlling extravascular hemolysis and improving hemoglobin levels.

Conclusions: The introduction of complement-inhibiting therapies has transformed classical PNH from a fatal disease into a manageable chronic condition. It is essential to optimize access to these treatments and ensure adequate prophylaxis against encapsulated infections. New drugs expand therapeutic options, further improving clinical outcomes and patients' quality of life.

Lipoprotein (a) [Lp(a)] levels are closely related to the development of ischemic heart disease in international studies; however, the impact on the severity of coronary and cardiac involvement in our country has not been described.

Hypothesis: High levels of Lp(a) are associated with greater involvement of coronary disease and ventricular function compromise.

Methods: Cross-sectional study among patients with ischemic heart disease admitted to a cardiac intensive care unit after acute coronary syndrome (ACS) or after coronary angioplasty for chronic coronary syndrome. Lipid profile and Lp(a) measurements were performed within the first 24 hours of admission, and echocardiogram with left ventricular ejection fraction (LVEF) measurement was performed within 5 days of admission. The magnitude of coronary disease (number of coronary arteries severely affected) and LVEF were evaluated in patients distributed according to Lp(a) levels considering a cut-off of 30 mg/dL and 50 mg/dL.

Results: One hundred and eighteen subjects were recruited, aged 65.9±20.2 years, 74.6% men, and 75% with ACS. Sixty patients (50.8%) were taking statins. Left anterior descending artery involvement was observed in 78.8%, with mean LVEF 49.9±17.5%, LDL 95.6±43.4 mg/dL (LDL >70 mg/dL in 69.4%), non-HDL 120.4±49.1 mg/dL, and Lp(a) 40.5±38.6 mg/dL. Lp(a) levels >30 mg/dL were detected in 42.3% and >50 mg/ dL in 27.9% of subjects. Lp(a) >30 mg/dL was associated with LVEF <40% (OR 2.6, p= 0.02), and values >50 mg/dL were related to LVEF <40% (OR 3.7, p= 0.03) and significant disease of 2 or more coronary arteries (OR 2.4, p= 0.04). Multivariate logistic regression analysis showed that Lp(a) levels >50 mg/dL were related to a higher risk of LVEF <40% (OR 3.8, p<0.01) and multivessel coronary disease (OR 2.8, p= 0.03).

Conclusion: In patients with established coronary heart disease, elevated Lp(a) levels are associated with a greater severity of coronary involvement and a lower LVEF.

We present the case of a 34-year-old male patient who consulted for genital lesions of 2 days evolution following unprotected sexual contact with his male partner 8 days prior. The physical examination revealed three white and umbilicated papules on the glans, foreskin, and pubis, as well as an ulcer on the foreskin. Initial tests yielded negative results, but a subsequent PCR test confirmed the infection with MPOX. MPOX is a zoonotic disease caused by an orthopoxvirus, with an increase in cases since 2016 and a declared public health emergency in 2022. The main transmission occurs through direct contact with secretions or lesions, primarily affecting men who have sex with men. The clinical course is similar to smallpox, with a prodromal stage followed by the appearance of cutaneous exanthema. It is important to highlight the possibility of diagnostic confusion with molluscum contagiosum, especially in initial stages. A precise diagnosis and appropriate treatment are crucial to avoid complications. In Chile, 1.441 confirmed cases of MPOX have been reported, with this being one of the few cases reported in the literature with initial presentation of molluscum contagiosum-like lesions in the genital area.

Tonsillar actinomycosis is a rare chronic disease that affects tonsillar tissue secondary to infection by anaerobic bacteria in the oral cavity. It usually presents as tonsillar hyperplasia and may mimic malignancy. We present the case of a patient referred from the pediatric department with severe unilateral tonsillar asymmetry with suspicion of malignancy. An imaging study showed tonsillar hyperplasia with no signs of local dissemination. The definitive diagnosis was made by excisional biopsy and histopathological study. An infectious disease evaluation indicated complementary treatment with high-dose penicillin-derived antibiotics, which achieved complete resolution of the clinical picture and no recurrent infections.

In a small percentage, multiple myeloma (MM) lacks a measurable monoclonal component, which is termed non-secretory (NS) MM, which includes oligosecretory, true NS and non-producing NS MM (NP). The latter is notable for complete and true absence of paraprotein production. We report a case of a 66-year-old male, studied for low back pain and vertebral lytic lesions, whose blood analysis showed only hypogammaglobulinemia, with no monoclonal component. However, the vertebral biopsy identified a plasma cell tumor. Bone marrow study showed pathological plasma cells without Kappa or Lambda production. With a diagnosis of MM NS NP, he received therapy, achieving complete remission. Extremely infrequently, this group presents a higher incidence of bone lesions and t(11;14) translocation. Therapy follows the general guidelines in MM. The difference lies in the follow-up, which considers myelogram and PET-CT, in addition to monitoring of organic damage.

Brucella canis infections are poorly understood in humans and difficult to diagnose, with low blood culture yields. Serological diagnosis was introduced in Chile in 2017.

Aim: To report a clinical series diagnosed by serological methods.

Methods: Multicenter study in southern Chile of cases admitted in three hospitals in two regions. Diagnosis was made by Rapid Slide Agglutination Test with 2-mercaptoethanol (ME-RSAT).

Results: Ten cases were identified between 2020 and 2024 (7 males, median age 54.5 years). Of these, 4 resided in rural areas, and 9 reported exposures to dogs. The cases presented as prolonged fever in 4 patients (40%), spondylodiscitis in 2 (20%), myopericarditis, meningoencephalitis, febrile hepatitis, and cervical lymphadenopathy with weight loss (10% each). Blood cultures were performed in 9 patients, all of which were negative (median incubation time 5 days). All 10 patients received treatment. Two were treated with doxycycline alone, while the remaining 8 received combination therapy. In 3 of the 10 cases, combination therapy was used to prevent relapse after a self-limiting episode of fever, myopericarditis or cervical lymphadenopathy. Histological analysis was available for 4 cases and 2 presented granulomas. The 7 patients who received treatment during the acute phase showed improvement. However, three of them developed chronic pain, and one patient required a disability pension. Additionally, the patient with hepatitis experienced three relapses. Human leucocyte antigen (HLA) typing showed a high relative frequency of the HLA B*07 allele. Epidemiological information reveals that most cases of brucellosis in Chile are due to B. canis, and are concentrated in southern regions.

Conclusions: B. canis infections are emerging, appear to be pleomorphic, with prolonged morbidity and risk of relapse and sequelae. A zoonotic exposure to dogs, even in the past, can help to in suspecting them, and diagnosis is primarily serological. They respond to treatments recommended for other Brucella species and may be associated to some HLA alleles.

Mpox (formerly known as monkeypox) is an emerging zoonosis caused by the Mpox virus (MPXV), which has raised global concern.

Aim: To explore and integrate the advances in the knowledge of the pathogenesis, clinical features, and therapeutic approaches to the Mpox virus in the context of our country.

Methods: A qualitative study through a narrative review of documents related to the international mpox epidemic.

Results: According to the search criteria and relevance, 10 articles were included. A general overview of the scientific evidence in microbiological and clinical aspects is presented, considering Chilean public health policies.

Conclusions: Clinicians should understand the pathogenesis, replication cycle, and clinical manifestations of MPXV to make an early diagnosis, develop therapeutic alternatives, and prevent its transmission within the community.