UNASSIGNED: Fever of unknown origin is quite common in everyday clinical practice, and the approach is challenging. Prolonged fever as the sole manifestation of craniopharyngioma has been rarely reported in literature.
UNASSIGNED: Herein, we report a case of adamantinomatous craniopharyngioma presented as fever of unknown origin in a 51-year-old woman, initially misdiagnosed as atypical subacute thyroiditis.
UNASSIGNED: During the work up, the patient complained about bitemporal hemianopsia. Thus, she underwent a pituitary Magnetic Resonance Imaging, which revealed a mixed mass originating from the pituitary stalk and compressing the optic chiasm. The mass was surgically excised, and the histology confirmed the diagnosis of adamantinomatous craniopharyngioma. The patient remained afebrile post-surgery. We hypothesize that the craniopharyngioma caused an abnormality of thermoregulatory mechanisms due to infiltration of the hypothalamus.

Fever of unknown origin (FUO) remains a formidable diagnostic challenge in the field of medicine. Numerous studies suggest an association between FUO and genetic factors, including chromosomal abnormalities. Here, we report a female patient with a 4.5 Mb Xp microdeletion, who presented with recurrent FUO, bacteremia, colitis, and hematochezia. To elucidate the underlying pathogenic mechanism, we employed a comprehensive approach involving single cell RNA sequencing, T cell receptor sequencing, and flow cytometry to evaluate CD4 T cells. Analysis of peripheral blood mononuclear cells revealed augmented Th1, Th2, and Th17 cell populations, and elevated levels of proinflammatory cytokines in serum. Notably, the patient exhibited impaired Treg cell function, possibly related to deletion of genes encoding FOPX3 and WAS. Single cell analysis revealed specific expansion of cytotoxic CD4 T lymphocytes, characterized by upregulation of various signature genes associated with cytotoxicity. Moreover, interferon-stimulated genes were upregulated in the CD4 T effector memory cluster. Further genetic analysis confirmed maternal inheritance of the Xp microdeletion. The patient and her mother exhibited X chromosome-skewed inactivation, a potential protective mechanism against extensive X chromosome deletions; however, the mother exhibited complete skewing and the patient exhibited incomplete skewing (85:15), which may have contributed to emergence of immunological symptoms. In summary, this case report describes an exceptional instance of FUO stemming from an incompletely inactivated X chromosome microdeletion, thereby increasing our understanding of the genetics underpinning FUO.

UNASSIGNED: Fever of unknown origin (FUO) has long been a cause for concern among clinicians, and its spectrum has evolved with progress in medicine. This study aimed to investigate the distribution of causes of FUO in China between 2013 and 2022 to facilitate the clinical understanding of the etiology of FUO.
UNASSIGNED: Case series of FUO in China published between 2013 and 2022 were retrieved from PubMed, Wanfang Data, and CNKI databases and retrospectively analyzed. The rates of different causes of FUO were calculated, and these data were compared with previously published distributions of causes of FUO in China.
UNASSIGNED: The causes of FUO with the highest rates from the 51 identified case series (n = 19,874) were infectious, autoimmune, and neoplastic diseases (59.6%, 14.3%, and 7.9%, respectively). A comparison of a subset (43 case series subdivided by disease category, n = 16,278) with previously reported data revealed an increased rate of FUO attributed to infectious diseases in the past decade, with a significantly higher rate attributed to bloodstream infections (10.0% vs. 4.8%) and a significantly lower rate attributed to tuberculosis (9.3% vs. 28.4%), compared with the rates from the previous period. In contrast, the rates of FUO attributed to both autoimmune and neoplastic diseases decreased, with significantly decreased rates attributed to adult-onset Still\'s disease among autoimmune diseases (4.6% vs. 8.5%) and lung cancer among neoplastic diseases (0.6% vs. 1.6%).
UNASSIGNED: Despite an overall increase in the rate attributed to infectious diseases, that attributed to tuberculosis has decreased. The rates attributed to both autoimmune and neoplastic diseases have also decreased.

Diagnosing neoplastic fever requires excluding identifiable causes, making it a diagnostic challenge. Fever as a primary manifestation of pancreatic adenocarcinoma is uncommon with few cases reported in the literature. Here we present an unusual case of metastatic pancreatic adenocarcinoma primarily manifesting as pyrexia of unknown origin. A 63-year-old Sri Lankan male, a non-smoker who was diagnosed with diabetes, hypertension and dyslipidaemia presented with a history of fever, anorexia and weight loss for 2 months. Despite the completion of treatment for positive serology for paratyphi, his symptoms and inflammatory markers remained elevated while the rest of the infectious screening was negative. On further evaluation, the patient was found to have a hypodense distal pancreas with ring-enhancing multiple liver lesions on imaging. Histology confirmed pancreatic adenocarcinoma with liver metastasis. Atypical liver metastases may present with evidence of ring enhancement in computed tomography imaging; thus, the biopsy is mandatory for diagnosis and decision-making. Usually, tumours of the pancreatic tail are resectable but if they are associated with liver metastatic disease, surgical resection is not recommended because it is not potentially curative. Therefore, in the context of metastatic pancreatic adenocarcinoma, palliative chemotherapy and pharmacological management of fever are required.

A 53-year-old otherwise healthy man was referred to our hospital with a fever of unknown origin, headache, and arthralgia. Four days earlier, he had a fever with chills. Treatment with antibiotics and acetaminophen proved ineffective, with the patient subsequently developing headache and joint pain. Blood analysis revealed elevated inflammatory markers, liver impairment, and severe thrombocytopenia (platelet count, 19,000/μL). Subsequent tests revealed elevated levels of anti-cytomegalovirus IgM and IgG. Based on these findings, the patient was diagnosed with severe thrombocytopenia associated with cytomegalovirus infection. Platelet counts increased spontaneously without antiviral therapy. Forty-five days after the initial visit, the symptoms improved, and blood tests revealed resolution of the inflammatory findings, with the platelet count recovering to 155,000/μL. Although the disease may resolve spontaneously, cytomegalovirus infection should be considered as a differential diagnosis in case of severe thrombocytopenia in immunocompetent adults.

BACKGROUND: Suspected infection or inflammation of unknown origin in in-patients remains challenging. Literature on [18F]FDG-PET/CT is abundant in classic fever of unknown origin (FUO), but evidence is complex and may not always reflect clinical reality. This study explores the application of [18F]FDG-PET/CT in a diverse clinical population of in-patients with suspected infection not defined by stringent FUO-criteria.
METHODS: Retrospective chart review of consecutive in-patients who underwent [18F]FDG-PET/CT in the workup of suspected infection or inflammation from 1 July 2022 to 31 December 2022 was conducted. We evaluated indications, diagnostic yield, and clinical impact of [18F]FDG-PET/CT, and compared the findings of [18F]FDG-PET/CT and stand-alone CT. Univariate logistic regression assessed associations between [18F]FDG-PET/CT outcome and clinical parameters. Receiver operating characteristic curve (ROC) analysis evaluated diagnostic performance.
RESULTS: 77 patients met the inclusion criteria. [18F]FDG-PET/CT established a diagnosis in 35% of cases, ruled out focal infection in 26%, and thus was helpful in 61% of patients. It prompted 72 additional examinations resulting in seven incidental diagnoses, including two cancers. Antibiotic treatment was changed in 26% of cases. Regression analysis found white blood cell counts (WBC) associated with true positive outcomes. [18F]FDG-PET/CT was compared to stand-alone CT findings, and was concordant in 69% of cases.
CONCLUSIONS: Results were comparable to findings in more classic FUO. [18F]FDG-PET/CT was clinically helpful in 61% of cases but also prompted many additional examinations with relatively few clinically important findings. WBC count was a predictor of true positive outcome. CT and [18F]FDG-PET/CT were discordant in 31%, of cases, especially in cases of endocarditis and spondylodiscitis.

UNASSIGNED: Fever of unknown origin (FUO) and inflammation of unknown origin (IUO) are syndromes commonly used as medical diagnoses. Since the existing literature has a mixture of diagnostic approaches, developing consensus-based recommendations would be helpful for clinicians, researchers, and patients.
UNASSIGNED: A modified Delphi process was performed from October 2022 to July 2023, involving 4 rounds of online surveys and 2 live video conferences. The panel comprised international experts recruited based on peer-reviewed published publications and studies.
UNASSIGNED: Among 50 invited experts, 26 (52.0%) agreed to participate. Twenty-three panelists completed round 1 of the survey, 21 completed rounds 2 and 3, 20 completed round 4, and 7 participated in round 5 live video discussions. Of the participants, 18 (78.3%) were academic-based clinicians and researchers, 5 (21.7%) practiced in a community-based hospital, and 6 (26.1%) were female. Consensus was reached on 5 themes: (1) incorporating epidemiologic factors, such as geographic location and travel history; (2) updated criteria for classifying FUO or IUO; (3) initial evaluation approaches; (4) a classification system for diagnoses; and (5) recommendations for judicious limitation of empiric therapies. Experts strongly disagreed with using 2-deoxy-2-[18F] fluoro-D-glucose positron emission tomography/computed tomography as part of the diagnostic criteria for FUO. There were mixed opinions about the importance of the temperature measurement site, the 3-week minimum illness criterion, the need for a standard definition of relapsing fevers, and the use of similar evaluation strategies for FUO and IUO.
UNASSIGNED: These Delphi-generated consensus-based recommendations offer potential improvements compared with earlier definitions and a guide for clinical practice and future research.

Still\'s disease is frequently a condition of exclusion for patients with an unidentified cause of fever. Accompanying symptoms typically include fever, arthralgia, and a transient skin rash. The underlying pathophysiology indicates an autoimmune origin. Diagnosis is primarily clinical, often utilizing the Yamaguchi criteria. The case in question involves a 19-year-old male presenting with high-grade fever and paralytic ileus. The patient received intravenous glucocorticoids and cyclophosphamide, resulting in a rapid clinical improvement. During the follow-up, tofacitinib was initiated based on the clinical response observed.

BACKGROUND: Nocardia is an ubiquitous soil organism. As an opportunistic pathogen, inhalation and skin inoculation are the most common routes of infection. Lungs and skin are the most frequent sites of nocardiosis. Testis is a highly unusual location for nocardiosis.
METHODS: We report the case of an immunocompromised 75-year-old-man admitted for fever of unknown origin. He presented with skin lesions after gardening and was first suspected of Mediterranean spotted fever, but he did not respond to doxycycline. Then, physical examination revealed new left scrotal swelling that was compatible with a diagnosis of epididymo-orchitis. The patient\'s condition did not improve despite empirical antibiotic treatment with the onset of necrotic scrotal abscesses requiring surgery. Nocardia brasiliensis yielded from the removed testis culture. High-dose trimethoprim-sulfamethoxazole and ceftriaxone were started. Multiple micro-abscesses were found in the brain and spinal cord on imaging studies. After 6 weeks of dual antibiotic therapy for disseminated nocardiosis, slight regression of the brain abscesses was observed. The patient was discharged after a 6-month course of antibiotics and remained relapse-free at that time of writing these lines. Trimethoprim-sulfamethoxazole alone is meant to be pursued for 6 months thereafter. We undertook a literature review on previously reported cases of genitourinary and urological nocardiosis; to date, only 36 cases have been published with predominately involvement of kidney, prostate and testis.
CONCLUSIONS: To the best of our knowledge, this is the first case of Nocardia brasiliensis simultaneously infecting skin, testis, brain and spinal cord in an immunocompromised patient. Knowledge on uncommon forms of nocardiosis remains scarce. This case report highlights the difficulty of diagnosing atypical nocardiosis and the importance of prompt bacteriological sampling in case of empirical antibiotics failure.

Melioidosis, an emerging infectious disease caused by the Gram-negative bacillus Burkholderia pseudomallei, is massively underdiagnosed in many low- and middle-income countries. The disease is clinically extremely variable, has a high case fatality rate, and is assumed to be highly endemic in South Asian countries, including Nepal. The reasons for underdiagnosis include the lack of awareness among clinicians and laboratory staff and limited microbiological capacities. Because costly laboratory equipment and consumables are likely to remain a significant challenge in many melioidosis-endemic countries in the near future, it will be necessary to make optimum use of available tools and promote their stringent implementation. Therefore, we suggest that health facilities in resource-poor countries, such as Nepal, introduce a simple and low-cost diagnostic laboratory algorithm for the identification of B. pseudomallei cultures. This screening algorithm should be applied specifically to samples from patients with fever of unknown origin and risk factors for melioidosis, such as diabetes. In addition, there could also be a role of low-cost, novel, promising serological point-of-care tests, which are currently under research and development.