PET/CT in the Evaluation of CAR-T Cell Immunotherapy in Hematological Malignancies.

Chimeric antigen receptor (CAR)-T cell-based immunotherapy has emerged as a path-breaking strategy for certain hematological malignancies. Assessment of the response to CAR-T therapy using quantitative imaging techniques such as positron emission tomography/computed tomography (PET/CT) has been broadly investigated. However, the definitive role of PET/CT in CAR-T therapy remains to be established. [18F]FDG PET/CT has demonstrated high sensitivity and specificity for differentiating patients with a partial and complete response after CAR-T therapy in lymphoma. The early therapeutic response and immune-related adverse effects such as cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome can also be detected on [18F]FDG PET images. In otherwise asymptomatic lymphoma patients with partial response following CAR-T therapy, the only positive findings could be abnormal PET/CT results. In multiple myeloma, a negative [18F]FDG PET/CT after receiving B-cell maturation antigen-directed CAR-T therapy has been associated with a favorable prognosis. In leukemia, [18F]FDG PET/CT can detect extramedullary metastases and treatment responses after therapy. Hence, PET/CT is a valuable imaging tool for patients undergoing CAR-T therapy for pretreatment evaluation, monitoring treatment response, assessing safety, and guiding therapeutic strategies. Developing guidelines with standardized cutoff values for various PET parameters and tumor cell-specific tracers may improve the efficacy and safety of CAR-T therapy.

Role of PET/CT in diagnosing and monitoring disease activity in rheumatoid arthritis: a review.

Rheumatoid Arthritis (RA) is a systemic inflammatory disorder that commonly presents with polyarthritis but can have multisystemic involvement and complications, leading to increased morbidity and mortality. The diagnosis of RA continues to be challenging due to its varied clinical presentations. In this review article, we aim to determine the potential of PET/CT to assist in the diagnosis of RA and its complications, evaluate the therapeutic response to treatment, and predict RA remission. PET/CT has increasingly been used in the last decade to diagnose, monitor treatment response, predict remissions, and diagnose subclinical complications in RA. PET imaging with [18F]-fluorodeoxyglucose ([18F]-FDG) is the most commonly applied radiotracer in RA, but other tracers are also being studied. PET/CT with [18F]-FDG, [18F]-NaF, and other tracers might lead to early identification of RA and timely evidence-based clinical management, decreasing morbidity and mortality. Although PET/CT has been evolving as a promising tool for evaluating and managing RA, more evidence is required before incorporating PET/CT in the standard clinical management of RA.

Chimeric antigen receptor T cell therapy for the treatment of systemic rheumatic diseases: a comprehensive review of recent literature.

Systemic rheumatoid diseases (SRDs) are autoimmune and inflammatory disorders that affect multiple organ systems, impacting patients' quality of life, and survival rates. Standard treatment requires continuous drug therapy and immunosuppression. Chimeric antigen receptor (CAR) T cell therapy has the potential to target and eliminate pathologically activated immune cells and re-establish tolerance in organs affected by dysregulated immunity, making them a promising treatment option for autoimmune diseases. In autoimmune diseases, CAR T cells have the advantage of being able to kill B cells effectively without the need for an accessory cell type. Additionally, CAR T cells targeting CD19 have shown promise in comprehensive B cell aplasia, preserving pre-existing humoral immunity, and specifically eliminating pathogenic B cells. CAR T cell therapy's limited use in SRDs is due to its inability to effectively target the various autoreactive lymphocytes present. Researchers are developing a universal CAR T cell therapy that detects and targets autoreactive lymphocytes using major epitope peptides, though further studies are required. Moreover, adoptive transfer of CAR-Tregs has shown promise for effectively reducing inflammation and treating autoimmunity. Through this exploration, the authors hope to provide a comprehensive understanding of the current state of research on this topic, identify areas for further study, and promote the advancement of CAR T cell therapy as a treatment option for SRDs.

Meningeal Signs and Cerebellar Involvement in Scrub Typhus: A Case Report.

Scrub typhus is an arthropod-borne fever that follows the bite of the larval form of Leptotrombidium mite carrying Orientia tsutsugamushi. It remains a serious health problem in the Asia-Pacific region. While it commonly presents as an undifferentiated fever with chills and an eschar, complications like pneumonitis, acute respiratory distress syndrome, disseminated intravascular coagulation, and meningoencephalitis may cause scrub typhus to be fatal. However, regardless of the dramatic presentation, treatment with antibiotics, preferably doxycycline or even azithromycin, is effective in recovery.  In this case report, we present a case of meningitis and cerebellar involvement in an adolescent with positive scrub typhus serology in the absence of an eschar. This brought forward a diagnostic delay as other infections including tuberculosis were considered before scrub typhus due to unusual presenting symptoms and the lack of an eschar. Thus, in cases like these, it becomes imperative to be aware of the unusual manifestations to initiate antibiotics on time and prevent further complications.

Drug-Induced Gum Overgrowth With Low-Dose Amlodipine: A Case Report.

Drug-induced gingival overgrowth is an adverse effect of certain drugs, including amlodipine, in genetically susceptible individuals. Although the exact mechanism of gingival hypertrophy remains unclear, a unifying multifactorial hypothesis has been constructed. Gingival hypertrophy causes difficulty in speech and mastication, poor oral hygiene, and poor aesthetic appearance. Here, we present the case of a 49-year-old woman who developed gum hypertrophy following amlodipine use for two years. Maintenance of oral hygiene and substitution of offending agent is commonly the first step in management.