Unexplained recurrent high fever observed in a depressed adolescent.

BACKGROUND: Depressive episodes in adolescents are often accompanied by various physical symptoms, but few studies have explored the association between depression and fever, This case study is the first to report the relationship between unexplained recurrent high fever and depression. CASE PRESENTATION: H is a 15 year old adolescent female currently in junior year. 2 + months ago, H gradually felt depressed after a class change. Around the time, the patient suddenly developed chills with no obvious trigger and fever. H was treated with anti-infective and anti-viral treatments all of which did not show significant improvement. No significant abnormality was seen in any of the related examinations. Considering that the patient's anxiety, depression and somatic symptoms were obvious during the course of the disease, she was given venlafaxine hydrochloride extended-release capsule 75 mg/d; tandospirone citrate capsule 10 mg Bid; alprazolam tablets 0.4 mg qn to improve mood and sleep; supplemented with transcranial repetitive magnetic stimulation therapy 2 times/d; visible light therapy 1 time/d and psychological counseling once. Over the 6 days of treatment, the patient's body temperature gradually returned to the normal range and her mood improved significantly. CONCLUSION: Depression should be considered a potential cause of unexplained recurrent fevers in adolescents, even when the temperature is significantly outside the normal range.

Barking up the wrong tree: Vascular tree-in-bud due to intravascular lymphoma.

A 59-year-old previously healthy woman presented with a six-month history of fever, nonproductive cough, and weight loss. The cause of these symptoms remained obscure despite a thorough, month-long hospitalization. On presentation, she was normotensive with a pulse of 98 beats/minute, respiratory rate of 20 breaths/minute, and a temperature of 39.4C. She was emaciated. Physical examination was notable for faint bibasilar crackles on lung auscultation. Initial laboratory testing revealed pancytopenia. Peripheral smear demonstrated normocytic, normochromic anemia without immature cells or schistocytes. Other notable laboratory findings included elevated levels of lactate dehydrogenase, elevated ferritin, and elevated levels of fasting serum triglycerides. A comprehensive laboratory evaluation for connective tissue disease was negative. Plain chest radiography was normal while computed tomography (CT) of the chest demonstrated sub-centimeter nodules in a branching centrilobular pattern as well as in a peri-lymphatic distribution without associated lymphadenopathy or organomegaly. The above constellation of laboratory abnormalities raised concern for hemophagocytic lymphohistiocytosis (HLH). Soluble IL-2 (CD25) receptor levels were markedly elevated. Bronchoscopy with transbronchial biopsies of the right lower lobe was performed, revealing intravascular lymphoma associated with HLH. Our case emphasizes the need for clinicians to consider vascular causes of tree - in-bud nodules in addition to the conventional bronchiolar causes. The case also is a reminder of the need to conduct an exhaustive search for malignancy, in patients with HLH.

Pulmonary and Urologic Sarcoidosis as a Cause of Intermittent Fever of Unknown Origin.

Diagnosing fever of unknown origin (FUO) presents a substantial challenge due to its potential association with various diseases affecting different organs. In 1961, Petersdorf and Beeson initially defined FUO as a condition characterized by a temperature exceeding 38.3 °C on at least three occasions over a minimum three-week period. Despite a week of inpatient investigation, a definitive diagnosis remains unclear.  Sarcoidosis, a granulomatous disease impacting multiple systems, is among the causes of FUO. While the lungs are commonly affected, any organ can be involved, leading to diverse manifestations and clinical courses. Diagnosis relies on clinicopathologic findings and the exclusion of alternative causes of granulomatous disease. The hallmark of sarcoidosis is the development of granulomas in affected organs. Here, we present the case of a 61-year-old man with a history of recurrent spontaneous periurethral abscesses who underwent multiple urological interventions. He developed FUO during hospitalization following treatment for the infectious condition.

Dengue en paciente de 32 días de vida. Reporte de un caso poco habitual / Dengue fever in a 32-day-old patient. A rare case report

El dengue es una enfermedad viral transmitida por la picadura del mosquito Aedes aegypti. El comportamiento del dengue en Argentina es epidémico; la mayoría de los casos se observan en los meses de mayor temperatura. Hasta la semana epidemiológica (SE) 20/2023, se registraron en Argentina 106 672 casos; se vieron afectadas 18 de las 24 provincias que conforman el país. Dentro de los principales grupos de riesgo, se incluyen los menores de 2 años. Reconocer los signos, síntomas e identificar los factores de riesgo es fundamental para el manejo de casos con mayor riesgo de gravedad. Presentamos el caso de una paciente de 32 días de vida que se internó por síndrome febril sin foco, con diagnósticos diferenciales de meningitis viral y sepsis, evolucionó con leucocitosis, plaquetopenia, hipoalbuminemia, asociado a exantema y edemas. Se llegó al diagnóstico de dengue por la clínica, epidemiologia e IgM positiva.

Dengue fever is a viral disease transmitted by the Aedes aegypti mosquitoes. In Argentina, dengue fever is an epidemic disease; most cases are reported during the hot months.Until epidemiological week (EW) 20/2023, 106 672 cases were reported across 18 of the 24 provinces of Argentina. Children younger than 2 years are among the main groups at risk. Recognizing signs and symptoms and identifying risk factors is fundamental for the management of cases at a higher risk of severity. Here we describe the case of a 32-day-old female patient who was hospitalized due to febrile syndrome without a source, who had a differential diagnosis of viral meningitis and sepsis and progressed to leukocytosis, thrombocytopenia, hypoalbuminemia in association with rash and edema. The diagnosis of dengue fever was established based on clinical, epidemiological, and positive IgM data.

The contribution of 18F FDG PET-CT for the investigation of fever of unknown origin and inflammation of unknown origin - systematic review and meta-analysis.

BACKGROUND: Fever of unknown origin and inflammation of unknown origin are highly challenging diagnostic conditions. The current practice for evaluating patients is to conduct a positron emission tomography-computed tomography (PET-CT) either as a first or as a second line modality. We aimed to assess the contributory effect of PET-CT to the diagnosis and compare it with the contributory effect of CT alone. METHODS: We performed a systematic review and meta-analysis. We included all cohorts that examined the contribution of PET-CT to the investigation of classical fever of unknown origin and inflammation of unknown origin. The primary outcome was the contribution of PET-CT to the final diagnosis. Secondary outcomes were sensitivity and specificity of PET-CT and CT scans, and contribution of a CT scan. We pooled the results of all studies and calculated the pooled contributory effect of PET-CT. RESULT: Thirty-six studies (3,516 patients) were included in the systematic review. The pooled contribution of PET-CT was 75.4%. The compiled sensitivity and specificity values for all studies were 85.9% and 59.5%, respectively. Five studies (405 patients) compared between the PET-CT component and the total body CT component. The pooled contribution of a CT scan was 68%. The summed sensitivity and specificity values of a CT scan for all studies were 63.1% and 84.4%, respectively. CONCLUSIONS: PET-CT has a contributory effect of 75% for the diagnosis of fever of unknown origin and inflammation of unknown origin. PET-CT had superior sensitivity and inferior specificity versus the CT scan.

Multidisciplinary Exploration of Unknown Oral Lesions With Accompanying Oral Verrucas of the Tongue: A Case Report.

A 64-year-old African American male with a history of hypertension and type II diabetes mellitus presented with unexplained upper lip lacerations after several frequent episodes of hemoptysis. Following the upper lip lacerations were several weeks of intermittent unknown episodic fevers. The patient, challenged by impaired mobility, exhibited an array of symptoms, including severe upper lip pain with lacerations and white patches on the tongue. Laboratory findings indicated thrombocytopenia and anemia, with positive tests for both influenza A and B. Despite completing Tamiflu, the patient experienced recurrent fevers. Imaging revealed gastrointestinal abnormalities, leading to the initiation of nystatin and a multi-antibiotic regimen without significant fever resolution. A subsequent tongue biopsy revealed verruca lesions, and acyclovir was initiated. Despite this, the patient developed lip and facial blisters. Negative results from cytomegalovirus (CMV) deoxyribonucleic acid (DNA) polymerase chain reaction (PCR) prompted a shift in focus to managing persistent fevers, ultimately controlled with naproxen but without discoverable cause. This case underscores the diagnostic challenge posed by unexplained fevers in an elderly patient with oral manifestations. The protracted course and evolving symptoms emphasize the intricacies of managing such cases, highlighting the need for continued investigation and collaboration across medical disciplines in navigating complex clinical scenarios.

Nuclear Medicine Imaging Tools in Fever of Unknown Origin (FUO): Time for a Revisit and Appropriate Use Criteria.

Fever of unknown origin (FUO) is a clinical conundrum for patients and clinicians alike and imaging studies are often performed as part of the diagnostic workup of these patients. Recently, the Society of Nuclear Medicine and Molecular Imaging (SNMMI) convened and approved a guideline on the use of nuclear medicine tools for FUO. The guidelines support the use of 2-18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) in adults and children with FUO. 18F-FDG PET/CT allows the detection and localization of foci of hypermetabolic lesions with high sensitivity, based on 18F-FDG uptake in glycolytically active cells that may represent inflammation, infection, or neoplasia. Clinicians should consider and insurers should cover 18F-FDG PET/CT when evaluating patients with FUO, particularly when other clinical clues and preliminary studies are unrevealing.

Secondary syphilis presenting as fever of unknown origin.

A thirty-eight year-old male presented with a seven-week history of persistent fever accompanied by recurrent night sweats, chills, arthralgias, headache, and chest tightness.Initial laboratory testing showed non-specific elevation of inflammatory markers, but was otherwise unremarkable.A palmar rash developed one week later, prompting testing for syphilis. Fluorescent treponemal antibody absorption (FTA-ABS) and rapid plasma reagin (RPR) tests were both positive.Penicillin G was administered and the patient recovered uneventfully.Our case emphasizes the need for increased syphilis screening to ensure proper diagnosis and prompt treatment.

Pyrexia of Unknown Origin: A Report of Two Cases.

Pyrexia of unknown origin (PUO) is a prolonged fever lasting several weeks without an identifiable cause despite extensive medical evaluation. Many a time, its cause remains largely unknown even after collecting a detailed medical history, conducting comprehensive physical assessments, and performing various standard laboratory tests and imaging procedures. This case series presents two cases of pyrexia of unknown origin. The first case includes a unique and uncommon presentation of non-Hodgkin's lymphoma. In the second case, the patient's fever remained unexplained after various investigations and treatments. The two documented cases of PUO presented in this report aim to contribute to the understanding of its diverse etiology and diagnostic challenges. By highlighting unique presentations and diagnostic dilemmas, the cases aim to promote awareness and facilitate timely recognition and appropriate management of PUO.

Unveiling the Mystery of Adult-Onset Still's Disease: A Compelling Case Report.

Adult-onset Still's disease (AOSD) is a rare systemic inflammatory disorder. Diagnosis can take a long time, especially in the presence of confounding factors, and it is, to some extent, a process of exclusion. AOSD has life-threating complications ranging from asymptomatic to severe, such as macrophage activation syndrome (MAS), which is also referred to as hemophagocytic lymphohistocytosis (HLH). This condition is correlated with cytokine storm production and monocyte/macrophage overactivation and typically occurs with rash, pyrexia, pancytopenia, hepatosplenomegaly and systemic involvement. Exitus occurs in approximately 10% of cases. For the treatment of MAS-HLH, the Histiocyte Society currently suggests high-dose corticosteroids, with the possible addition of cyclosporine A, anti-interleukin (IL)-1, or IL-6 biological drugs; the inclusion of etoposide is recommended for the most severe conditions. In all cases, a multidisciplinary collaboration involving the resources and expertise of several specialists (e.g., rheumatologist, infectiologist, critical care medicine specialist) is advised. Herein, we provide a detailed description of the clinical case of a previously healthy young woman in which MAS developed as a dramatic onset manifestation of AOSD and whose diagnosis posed a real clinical challenge; the condition was finally resolved by applying the HLH-94 protocol (i.e., etoposide in combination with dexamethasone).

Development of a Consensus-Based List of Potential Quality Indicators for Fever and Inflammation of Unknown Origin.

With a growing emphasis on value-based reimbursement, developing quality indicators for infectious diseases has gained attention. Quality indicators for fever of unknown origin and inflammation of unknown origin are lacking. An assembled group of international experts developed 12 quality measures for these conditions, which could be validated with additional study.

Characteristics of Functional Hyperthermia Detected in an Outpatient Clinic for Fever of Unknown Origin.

Background: Functional hyperthermia (FH) is characterized by hyperthermia resulting from sympathetic hyperactivity rather than inflammation, and it is frequently overlooked by medical practitioners due to the absence of abnormalities in a medical examination. Although FH is an important differential diagnosis for fever of unknown origin (FUO), the literature on FUO cases in Japan lacks information on FH. In this study, we aimed to uncover the population of FH patients hidden in FUO cases. Methods: An outpatient clinic for FUO was established at Okayama University Hospital, and 132 patients were examined during the period from May 2019 to February 2022. Results: A diagnosis of FH was made in 31.1% of the FUO cases, and FH predominantly affected individuals in their third and fourth decades of life with a higher incidence in females (68.3%). The frequency of a history of psychiatric illness was higher in patients with FH than in patients with other febrile illnesses. Although the C-reactive protein (CRP) is generally negative in FH cases, some obese patients, with a body mass index ≥ 25 had slightly elevated levels of CRP but were diagnosed with FH. Conclusions: The results showed the importance of identifying FH when encountering patients with FUO without any organic etiology.

A Rare Case of Acute Myeloid Leukemia Initially Presenting With Fever of Unknown Origin and Rapidly Progressing Pericardial Effusion.

This case report highlights a patient who had persistent fevers for weeks and rapidly progressing pericardial effusion following a positive test for coronavirus disease 2019 (COVID-19) two weeks before presentation to the hospital. The initial thought was that her fever was of infectious etiology, but relevant investigations led to the diagnosis of acute myeloid leukemia (AML). AML, which is characterized by clonal expansion of immature "blast cells" in the peripheral blood and bone marrow resulting in ineffective erythropoiesis and bone marrow failure, is the most prevalent form of leukemia. It is the most aggressive form of leukemia, which has varying prognoses determined by the subtypes. This report explores the association between AML, fever of unknown origin, and pericardial effusion, shedding light on a notable clinical aspect. Fever in AML may be attributed to underlying inflammatory processes, cytokine dysregulation, or bone marrow failure. Recognition of fever as a potential indicator of AML contributes to enhanced clinical vigilance. Pericardial effusions and cardiac tamponade, although rare, can be a presenting feature of AML, and can present side by side with fever of unknown origin as seen in this case report.

The yield of total body CT in the workup of fever of unknown origin in hospitalized medical patients.

INTRODUCTION: Total body computerized tomography (TBCT) is frequently used as a diagnostic tool for fever of unknown origin (FUO) workup instead of a recommended fluorodeoxyglucose positron emission tomography FDG-PET/CT. We have assessed the TBCT diagnostic yield on a large, unselected cohort of patients with FUO. METHODS: We performed a single-center retrospective cohort study, examining all patients hospitalized in internal medicine between 2012 and 2019 with a documented fever and three negative blood cultures who subsequently had a total-body CT performed. After manually reviewing, we included 408 who met the criteria of FUO. We defined a positive study as a scan that led to the documented final diagnosis. RESULTS: A total of 164 patients (40.2 %) had a positive TBCT result. The majority of positive CT findings were of infectious etiologies (58.5 %), followed by neoplasms (22.8 %) and inflammatory disorders (14.0 %), with the chest (43.9 %) and abdomen (29.8 %) most affected. Using a logistic regression model, a positive scan results were associated with an elevated CRP (p<0.001). Decision tree analysis showed that 55 % of scans of patients with an elevated CRP (>6 mg/dL), low hemoglobin and high leucocyte count (>18000/ml) were positive. Patients without an elevated CRP had a positive scan in only 26 % of tests, and those with also an elevated albumin (>4 gr/dL) and low CRP had positive scan in only 11 % of cases. CONCLUSIONS: TBCT has a clinically significant yield under specific clinical scenarios in medical patients with FUO- reaching 55 % in patients with an elevated CRP and leukocyte count and low hemoglobin. It is reasonable to proceed to TTBCT when FDG-PET/CT is unavailable and in well-defined clinical situations.

Significance of F-18 FDG PET/MRI in the search for the etiology of inflammation of unclear origin and fever of unknown origin.

PURPOSE: To evaluate the contribution of F-18 FDG-PET/MRI in the search for the etiology of the inflammation of unknown origin (IUO) and fever of unknown origin (FUO). MATERIAL AND METHODS: The study included 104 patients who underwent F-18 FDG-PET/MRI for IUO or FUO. The sensitivity, specificity, predictive values of the PET/MRI findings in relation to the final diagnosis of IUO/FUO were evaluated. A five-point Likert scale was used to semiquantitatively assess the probability of the cause of IUO/FUO based on PET/MRI finding. Furthermore, clinical (fever, arthralgia, weight loss, night sweats, age) and laboratory (C-reactive protein, leukocytes) parameters were monitored and compared with the true positivity rate of PET/MRI. RESULTS: In patients with definitively identified etiology of FUO and IUO, FDG-PET/MRI achieved a sensitivity of 96 %, specificity of 82 %, and positive and negative predictive values of 92 and 90 %. The cause of the IUO was determined in 71 patients (68.3 %). In 33 (31.7 %) patients, the etiology of IUO/FUO remained unknown, while in 25 (75.8 %) of them the symptoms resolved spontaneously and in 8 (24.2 %) patients they persisted without explanation even after 12 months of the follow-up. The most significant parameter in relation to subsequent PET/MRI finding was increased level of CRP, which was present in 96 % of true positive PET/MRI and normal CRP level was present in 56 % of true negative PET/MRI. CONCLUSION: Based on this study, FDG-PET/MRI is a suitable alternative for the investigation of IUO/FUO, this imaging technique has a very high sensitivity and negative predictive value.

Infectious causes of fever of unknown origin in developing countries: An international ID-IRI study.

Background: Fever of unknown origin (FUO) in developing countries is an important dilemma and further research is needed to elucidate the infectious causes of FUO. Methods: A multi-center study for infectious causes of FUO in lower middle-income countries (LMIC) and low-income countries (LIC) was conducted between January 1, 2018 and January 1, 2023. In total, 15 participating centers from seven different countries provided the data, which were collected through the Infectious Diseases-International Research Initiative platform. Only adult patients with confirmed infection as the cause of FUO were included in the study. The severity parameters were quick Sequential Organ Failure Assessment (qSOFA) ≥2, intensive care unit (ICU) admission, vasopressor use, and invasive mechanical ventilation (IMV). Results: A total of 160 patients with infectious FUO were included in the study. Overall, 148 (92.5%) patients had community-acquired infections and 12 (7.5%) had hospital-acquired infections. The most common infectious syndromes were tuberculosis (TB) (n=27, 16.9%), infective endocarditis (n=25, 15.6%), malaria (n=21, 13.1%), brucellosis (n=15, 9.4%), and typhoid fever (n=9, 5.6%). Plasmodium falciparum, Mycobacterium tuberculosis, Brucellae, Staphylococcus aureus, Salmonella typhi, and Rickettsiae were the leading infectious agents in this study. A total of 56 (35.0%) cases had invasive procedures for diagnosis. The mean qSOFA score was 0.76±0.94 {median (interquartile range [IQR]): 0 (0-1)}. ICU admission (n=26, 16.2%), vasopressor use (n=14, 8.8%), and IMV (n=10, 6.3%) were not rare. Overall, 38 (23.8%) patients had at least one of the severity parameters. The mortality rate was 15 (9.4%), and the mortality was attributable to the infection causing FUO in 12 (7.5%) patients. Conclusions: In LMIC and LIC, tuberculosis and cardiac infections were the most severe and the leading infections causing FUO.

Utility of metagenomic Next-Generation Sequencing for simultaneously detecting pathogens and neoplasms.

Objectives: Clinicians often face the challenge of differentially diagnosing febrile patients who are suspected of infectious diseases, since the clinical manifestations of infection and cancer may overlap. A single test that can detect both pathogens and tumor could provide timely and accurate diagnostic clues to aid the treatment and management of these patients. Methods: We enrolled eight patients to evaluate the utility of metagenomic Next-Generation Sequencing for simultaneously detecting pathogens and neoplasms using body fluids and tissue samples. Patients were selected by the following criteria: 1) Tumor was not considered upon hospitalization, but mNGS testing indicated neoplasm; 2) Tumor was not excluded, but microbial infection was primarily suspected according to initial clinical assessment. Results: We detected potential pathogens in five patients, three of whom had progressed into critical infections. Moreover, abnormal chromosomal copy numbers were identified in all patients that indicated presence of neoplasms, which were pathologically confirmed. Conclusions: Although copy number variations do not render a definitive cancer diagnosis, it can prompt clinicians to conduct more focused diagnostic testing for cancer, potentially saving time and cost. As a result, integrating copy number analysis with pathogen detection in mNGS may help establish rapid and accurate diagnosis for febrile patients.

An Unusual Case of Sarcoidosis with a Prolonged Fever and Progressive Arthropathy.

A 70-year-old man had developed a high fever and arthralgia in his right elbow 6 months prior. Loxoprofen improved the symptoms temporarily, but arthropathy developed in other joints. Long-term recurrent arthropathy and the fever caused activity reduction and progressive debilitation. We performed fluorine-18 fluorodeoxyglucose-positron emission tomography and detected a positive accumulation in multiple joints and lymph nodes. A lymph node biopsy revealed epithelioid cell granulomas, which, along with elevated angiotensin-converting enzyme levels, led to the diagnosis of sarcoid arthropathy. After prednisolone administration, the fever and arthralgia resolved, and his activities of daily living improved. Clinicians should be aware of this type of sarcoid arthropathy.

Dengue fever in a 32-day-old patient. A rare case report. / Dengue en paciente de 32 días de vida. Reporte de un caso poco habitual.

Dengue fever is a viral disease transmitted by the Aedes aegypti mosquitoes. In Argentina, dengue fever is an epidemic disease; most cases are reported during the hot months. Until epidemiological week (EW) 20/2023, 106 672 cases were reported across 18 of the 24 provinces of Argentina. Children younger than 2 years are among the main groups at risk. Recognizing signs and symptoms and identifying risk factors is fundamental for the management of cases at a higher risk of severity. Here we describe the case of a 32-day-old female patient who was hospitalized due to febrile syndrome without a source, who had a differential diagnosis of viral meningitis and sepsis and progressed to leukocytosis, thrombocytopenia, hypoalbuminemia in association with rash and edema. The diagnosis of dengue fever was established based on clinical, epidemiological, and positive IgM data.

El dengue es una enfermedad viral transmitida por la picadura del mosquito Aedes aegypti. El comportamiento del dengue en Argentina es epidémico; la mayoría de los casos se observan en los meses de mayor temperatura. Hasta la semana epidemiológica (SE) 20/2023, se registraron en Argentina 106 672 casos; se vieron afectadas 18 de las 24 provincias que conforman el país. Dentro de los principales grupos de riesgo, se incluyen los menores de 2 años. Reconocer los signos, síntomas e identificar los factores de riesgo es fundamental para el manejo de casos con mayor riesgo de gravedad. Presentamos el caso de una paciente de 32 días de vida que se internó por síndrome febril sin foco, con diagnósticos diferenciales de meningitis viral y sepsis, evolucionó con leucocitosis, plaquetopenia, hipoalbuminemia, asociado a exantema y edemas. Se llegó al diagnóstico de dengue por la clínica, epidemiologia e IgM positiva.

FDG-PET/CT for investigation of pyrexia of unknown origin: a cost of illness analysis.

BACKGROUND: Our study aims to explore the current utilisation of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in the diagnostic pathway of pyrexia of unknown origin (PUO) and associated cost of illness in a large tertiary teaching hospital in Australia. METHOD: 1257 febrile patients between June 2016 and September 2022 were retrospectively reviewed. There were 57 patients who met the inclusion criteria of "classical PUO", of which FDG-PET/CT was performed in 31 inpatients, 15 outpatients and 11 inpatients did not have an FDG-PET/CT scan. The patient demographics, clinical characteristics and inpatient cost were analysed, together with the diagnostic performance of FDG-PET/CT and impact on clinical management. RESULT: The mean age, length of stay and total cost of admission were higher for inpatients who received FDG-PET/CT versus those who did not. The median cost per patient-bed-day did not differ between the two groups. Inpatients who received earlier FDG-PET/CTs (≤ 7 days from admission) had shorter length of stays and lower total cost compared to those who received a later scan. A negative FDG-PET/CT scan, demonstrating no serious or life-threatening abnormalities resulted in subsequent discharge from hospital or outpatient clinic in 7/10 (70%) patients. There were 11/40 (28%) scans where ancillary abnormalities were identified, requiring further evaluation. CONCLUSION: FDG-PET/CT showed high diagnostic accuracy and significant impact on patient management in patients with PUO. FDG-PET/CT performed earlier in admission for PUO was associated with shorter length of stay and lower total cost.