Establishment and evaluation of a CT-based radiomic model for AIDS-associated pulmonary cryptococcosis.

BACKGROUND: Establish a CT-based diagnostic radiomic model for AIDS complicated with pulmonary cryptococcosis and evaluate the diagnostic efficacy of this model. METHODS: This retrospective study enrolled 98 AIDS patients with pulmonary cryptococcosis and 103 AIDS patients with other infections or neoplastic lesions, comprising a total of 699 lesions. Patients were randomly divided into a training group and test group at a ratio of 2.75:1. Features from all lesions, cavity lesions and solid nodule lesions were extracted, and two kinds of radiomic models (6 types) were established. ROC curves were drawn, and the sensitivity and specificity were calculated to compare the SVM model and LR model, radiologists' empirical diagnoses and the combination of these empirical diagnoses with the radiomic model. RESULTS: The AUCs of senior radiologist for all lesions and cavity lesions were lower than those of the SVM and LR models. The diagnostic efficacy of primary radiologist was lower than that of both of the other model types. The diagnostic efficacy of the LR model was relatively stable, with the highest diagnostic efficiency of the 3 model/radiologist groups. The AUCs of intermediate radiologist in combination with the LR radiomic model for all lesions, nodular lesions and cavity lesions were 0.88, 0.84, and 0.9, respectively, which were the highest among all models and radiologists. CONCLUSIONS: The CT-based radiomic LR model of AIDS-associated pulmonary cryptococcosis exhibits good diagnostic performance, which was similar to that of senior radiologists and higher than that of the primary radiologist. With the help of a radiomic model, radiologists can achieve improved diagnostic accuracy compared to that when only an empirical diagnosis is used.

Disseminated intraosseous Kaposi's sarcoma: A rare manifestation of HIV/AIDS.

Kaposi Sarcoma (KS), a mucocutaneous cancer that most frequently occurs in the context of Acquired Immunodeficiency Syndrome (AIDS) secondary to Human Immunodeficiency Virus (HIV), is a relatively benign condition, acting more as a marker of immunodeficiency than directly causing harm itself. However, it has been known to spread both locally and in a metastatic fashion, with reports of KS affecting almost all organ systems. One of the most rarely reported areas of involvement is the musculoskeletal system, with secondary osseous spread representing an even smaller subset of these. We report a case of biopsy proven disseminated intraosseous KS involving the entire imaged skeleton that occurred with HIV/AIDS, despite maximal treatment and normal imaging 8 months prior.

Selected nanotechnologies and nanostructures for drug delivery, nanomedicine and cure.

The development of nanoparticle-based drugs has provided many opportunities to diagnose, treat and cure challenging diseases. Through the manipulation of size, morphology, surface modification, surface characteristics, and materials used, a variety of nanostructures can be developed into smart systems, encasing therapeutic and imaging agents with stealth properties. These nanostructures can deliver drugs to specific tissues or sites and provide controlled release therapy. This targeted and sustained drug delivery decreases the drug-related toxicity and increases the patient's compliance with less frequent dosing. Nanotechnology employing nanostructures as a tool has provided advances in the diagnostic testing of diseases and cure. This technology has proven beneficial in the treatment of cancer, AIDS, and many other diseases. This review article highlights the recent advances in nanostructures and nanotechnology for drug delivery, nanomedicine and cures.

Multiple Extradural Spinal Meningiomas in a Patient with Acquired Immunodeficiency Syndrome: Case Report and Literature Review.

BACKGROUND: Purely extradural spinal meningiomas are uncommon. Due to their typical location in the neural foramen, they are often mistaken for schwannomas, neurofibromas, and epidural metastases. In addition, comorbid conditions such as immunodeficiency may obscure the diagnosis. We present a case of extradural spinal meningiomas in a patient with human immunodeficiency virus (HIV). This is the first reported case of multiple extradural spinal meningiomas in 2 separate regions of the spine. CASE DESCRIPTION: A 40-year-old male with a past medical history of HIV and hepatitis B infection presented with a 2-month history of progressive back pain radiating to the left flank and thigh. Magnetic resonance imaging of the thoracic and lumbar spine with intravenous gadolinium contrast revealed 2 extramedullary masses in the left neural foramina of T6 and L1. The patient underwent laminectomy, which revealed that the 2 lesions were entirely extradural. Both lesions were resected, and the histological diagnosis for both lesions was meningioma, World Health Organization grade I. CONCLUSIONS: Our experience with this 40-year-old male with AIDS who presented with radicular symptoms due to multiple purely extradural meningiomas underscores the importance of considering meningioma as a possible diagnosis in patients with tumors of the neural foramina. In addition, a wide differential diagnosis should be made for patients with spinal lesions and history of HIV, including illnesses that are related to immunodeficiency and those that are not.

AIDS Presenting as Granulomatous Amebic Encephalitis: PET and MR Imaging correlation.

Granulomatous amebic encephalitis (GAE) is a rare and oftentimes fatal disease in immune compromised patients caused by free living amebae Acanthamoeba and Balamuthia. We report a patient in whom GAE secondary to Acanthamoeba was the initial presentation of acquired immunodeficiency syndrome in a 41-year-old male, and discuss the FDG positron emission tomography (PET) and magnetic resonance imaging findings that preceded the pathological diagnosis. The PET results provided complementary information when coupled with the MR brain findings. Improved understanding of the clinical and imaging findings of this deadly disease is the best hope for early diagnosis and treatment of this uncommon but deadly disease.

Apical Pneumocystis jiroveci as an AIDS defining illness: A case report illustrating a change in the paradigm.

Pneumocystis jiroveci pneumonia is a common acquired immune deficiency syndrome defining illness. Pneumocystis jiroveci pneumonia is classically described as having symmetrical bilateral perihilar ground-glass opacities on chest radiographs. We present an "atypical" case of Pneumocystis jiroveci pneumonia presenting as symmetric biapical cystic spaces with relative sparing of the remainder of the lungs in a 22 year-old male, previously undiagnosed with acquired immune deficiency syndrome. Our case illustrates that formerly unusual presentations of Pneumocystis jiroveci pneumonia are becoming more common as acquired immune deficiency syndrome defining illnesses as more patients are being imaged with further imaging such as high resolution computed tomography.

Pulmonary cryptococcosis in rheumatoid arthritis (RA) patients: comparison of imaging characteristics among RA, acquired immunodeficiency syndrome, and immunocompetent patients.

PURPOSE: The imaging characteristics of cryptococcosis in rheumatoid arthritis (RA) patients were analyzed by comparing them with those of acquired immunodeficiency syndrome (AIDS) and immunocompetent patients, and the imaging findings were correlated with pathological findings. METHODS: Two radiologists retrospectively compared the computed tomographic (CT) findings of 35 episodes of pulmonary cryptococcosis in 31 patients with 3 kinds of underlying states (10 RA, 12 AIDS, 13 immunocompetent), focusing on the nature, number, and distribution of lesions. The pathological findings of 18 patients (8 RA, 2 AIDS, 8 immunocompetent) were analyzed by two pathologists, and then correlated with imaging findings. RESULTS: The frequencies of consolidation and ground glass attenuation (GGA) were significantly higher, and the frequency of peripheral distribution was significantly lower in the RA group than in the immunocompetent group. Peripheral distribution was less common and generalized distribution was more frequent in the RA group than in the AIDS group. The pathological findings of the AIDS and immunocompetent groups reflected their immune status: There was lack of a granuloma reaction in the AIDS group, and a complete granuloma reaction in the immunocompetent group, while the findings of the RA group varied, including a complete granuloma reaction, a loose granuloma reaction and a hyper-immune reaction. Cases with the last two pathologic findings were symptomatic and showed generalized or central distribution on CT. CONCLUSION: Cryptococcosis in the RA group showed characteristic radiological and pathological findings compared with the other 2 groups.

Imaging of miscellaneous pancreatic pathology (trauma, transplant, infections, and deposition).

In this article's coverage of miscellaneous pancreatic topics, a brief review of pancreatic trauma; pancreatic transplantation; rare infections, such as tuberculosis; deposition disorders, including fatty replacement and hemochromatosis; cystic fibrosis; and others are discussed with pertinent case examples.

AIDS complicated with intestinal lymphoma: X-ray radiology, CT scan and pathological findings.

BACKGROUND: The non-Hodgkin's lymphoma is the AIDS symbol of tumor, with high incidence and poor prognosis. The purpose of this study was to investigate the radiological demonstrations of AIDS complicated by intestinal lymphoma and its pathological mechanism. METHODS: CT scan and pathological data of 3 cases of AIDS complicated by intestinal lymphoma were retrospectively analyzed. All the 3 cases received CT diagnostic scanning, including 2 receiving barium enema radiography after lower gastrointestinal tract cleansing, 1 receiving laporotomy to obtain partial thickened intestinal canal for histopathology and 1 with autopsy for histopathological analysis. RESULTS: Intestinal canal lymphoma occurred at the left intestinal canal in 2 cases and at the right intestinal canal in the other case, with manifestations of unevenly thickened intestinal canal wall, narrowed canal lumen and filling defect. It was pathologically classified as B cell lymphoma. CONCLUSIONS: AIDS complicated by B cell lymphoma has manifestations of unevenly thickened intestinal canal wall and narrowed canal lumen, which are non-specific. It should be differentiated from other tumors of intestinal canal in its diagnosis.

Imaging and pathological findings of AIDS complicated by pulmonary Rhodococcus equi infection.

BACKGROUND: Rhodococcus equi (R. equi) infection commonly occurs in grazing areas, especially in patients with AIDS or with T-lymphocyte immuno-deficiencies. Literature reviews revealed that cases radiologically and pathologically diagnosed of AIDS complicated by R. equi infection are rare. This study aimed to investigate the imaging features and pathological basis of AIDS complicated by pulmonary R. equi infection. METHODS: A total of 13 cases of AIDS complicated by pulmonary R. equi infection were retrospectively analyzed based on their imaging, bacterial culture and pathological data, including 10 cases by chest CT scanning and X-ray radiology and 3 cases by only X-ray radiology. All 13 cases were definitely diagnosed by bacterial culture, including one by CT-guided pulmonary puncture with following H&E staining and periodic acid-Schiff (PAS) staining for diagnostic biopsy and another one by bronchial biopsy with following H&E staining and PAS staining for pathological diagnosis. The imaging findings and the pathological findings of AIDS complicated by pulmonary R. equi infection were compared and evaluated. RESULTS: Totally 9 subjects (70%) had radiological demonstrations of central ball liked high density shadows in unilateral pulmonary hilus areas; 10 (77%), cavities and liquefied levels; 3 (23%), pleural effussion. The foci were found in pulmonary inner zone in 10 subjects (77%) and in pulmonary outer zone in one subject (7%). The pathological findings included intra-alveolar hemorrhage, lymphocyte infiltration and granulation tissue proliferation, which were in line with the pathological process of necrotic pneumonia. After 8-month follow-up of anti-R. equi therapy of these 13 cases, 9 cases had obviously decreased or shrunk pulmonary cavities, one died, one missed follow-up, one completely absorbed foci and one did not receive reexaminations. CONCLUSIONS: The radiological demonstrations of AIDS complicated by pulmonary R. equi infection are central ball liked high density areas in unilateral pulmonary hilus area, parenchymal changes, secondary cavities, ground glass liked changes in the lung fields, nodules and treeinbuds sign, which are characteristic rather than specific.

PET/CT scanning with a high HIV/AIDS prevalence.

Positron emission tomography (PET) with [F-18]-fluoro-deoxy-glucose (FDG) has a well established and growing role in the management of most lymphomas. The interpretation of FDG PET scans in HIV positive patients is however challenging. This is largely due to scan changes giving a higher likelihood of false positive studies from both the direct effects of HIV and its treatment, and related to secondary HIV-related pathology. There is currently a need for further clinical research to evaluate to contribution of FDG PET in the management of HIV positive patients with lymphoma. In this paper existing studies related to FDG PET scanning in HIV positive patients will be reviewed, and potential pitfalls will be identified. These pitfalls can be avoided to some extent by the interpreter having a good clinical knowledge of the individual patients' condition, and an awareness of known scintigraphic patterns that can occur in these patients. PET remains a sensitive tool for the localisation of pathology, however when the exact nature of lesions has a direct bearing on patient management lesions need to be biopsied where possible. FDG PET can be particularly useful for the characterisation of brain lesions suspected to be related to primary central nervous system lymphoma.

Granulomatous reaction to pneumocystis jirovecii: clinicopathologic review of 20 cases.

To better characterize the clinical and pathologic features of granulomatous reaction to Pneumocystis jirovecii, we reviewed 20 cases of this uncommon response. Patients included 15 males and 5 females (mean age 52 y). The most common symptom was dyspnea (5 of 14). Primary medical diagnoses included human immunodeficiency virus/acquired immunodeficiency syndrome (7 of 20), hematopoietic (6 of 20), and solid malignancies (4 of 20). Radiology findings included nodular (8 of 16) and diffuse (5 of 16) infiltrates and solitary nodules (3 of 16). Diagnostic procedures with the highest yield were open lung biopsy (13 of 20) and autopsy (5 of 20); false-negative results were most common on bronchial washings/brushings, bronchoalveolar lavage, fine needle aspiration, and transbronchial biopsy. Follow-up showed resolution of disease (6 of 13), death from disease (6 of 13), and death from unknown cause (1 of 13). Histologically, clusters of Gomori methenamine silver-positive (20 of 20) Pneumocystis organisms were identified in all cases. Organisms were identified within well (16 of 20) and poorly (4 of 20) formed necrotizing (16 of 20) and non-necrotizing (4 of 20) granulomas ranging in size from 0.1 to 2.5 cm (mean 0.5 cm); granulomas were multiple (18 of 20) or single (2 of 20). Giant cells (11 of 20), a fibrous rim (8 of 20), and eosinophils (6 of 20) were seen. Foamy eosinophilic exudates were present centrally within some granulomas (5 of 20). Cystic spaces (1 of 20) and calcification (1 of 20) were rare. Only one case demonstrated classic intra-alveolar foamy exudates containing Pneumocystis. Granulomatous P. jirovecii pneumonia occurs most commonly in males with human immunodeficiency virus/acquired immunodeficiency syndrome, hematopoietic, and solid malignancies. The diagnosis may be overlooked as conventional radiologic and pathologic features are absent. When suspected, open lung biopsy is most likely to yield diagnostic material. Attention to organism morphology avoids misdiagnosis as Histoplasma.

Imaging features of CNS involvement in AIDS.

Patients with acquired immunodeficiency syndrome (AIDS) are the subjects of a large part of routine neuroradiological work in the Western world currently. The World Health Organization announced that Turkish authorities had reported a cumulative total of 2544 HIV cases from 1985 to 2006, of whom 623 had developed AIDS and 140 had died. It is estimated that approximately one-third of AIDS patients develop neurological complications. The spectrum of diseases affecting the central nervous system (CNS) in AIDS patients comprises predominantly opportunistic infections and primary CNS lymphoma. Although to a lesser degree when compared with Western countries, the incidence of AIDS and related neurological diseases are on the rise also in Turkey. Therefore radiologists should recognize HIV-associated problems and their imaging features. In this review, we focus on imaging features of more common CNS diseases in HIV-seropositive patients. This essay has been prepared using radiological studies of the patients who had been managed in our hospital which is a tertiary care center with a highly motivated medical team for this peculiar disease in the years between 2002 and 2008.

Positron emission tomography as a diagnostic tool in infection: present role and future possibilities.

The past decade has witnessed the emergence of yet another promising application of (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) imaging in the detection and management of patients with infection and inflammatory disorders. This phenomenon is quite evident when the peer-reviewed scientific literature is searched for on this topic. Among these scientific communications, the 6 conditions in which FDG-PET has demonstrated its greatest utility include (1) chronic osteomyelitis, (2) complicated lower-limb prostheses, (3) complicated diabetic foot, (4) fever of unknown origin, (5) acquired immunodeficiency syndrome (ie, AIDS), and (6) vascular graft infection and fistula. On the basis of published literature, orthopedic infections, particularly those related to implanted prostheses and osteomyelitis (including that occurring in the setting of a complicated diabetic foot), can be detected successfully by the use of FDG-PET and, therefore, this modality has great promise for becoming the study of choice in these complex settings. Increasingly, this technique is being used to detect infection in soft tissues, including those representing the sources of fever of unknown origin. The ability of FDG-PET to diagnose vascular graft infection and fistula, even when the anatomical imaging modalities are inconclusive, is of considerable interest to practitioners of vascular surgery. Combined PET/computed tomography (CT) imaging has the potential to determine the sites of infection or inflammation with high precision. The data on the role of PET/CT imaging in the assessment of infection and inflammation is sparse, but this combined modality approach may prove to be the study of choice in foreseeable future for precise localization of involved sites. However, the role of PET/CT may be limited in the presence of metallic artifacts (such as those caused by prostheses) adjacent to the sites of infection.

Low CD4+ T-cell count as a major atherosclerosis risk factor in HIV-infected women and men.

OBJECTIVE: To assess the association of HIV infection, HIV disease parameters (including CD4+ T-cell counts, HIV viral load, and AIDS) and antiretroviral medication use with subclinical carotid artery atherosclerosis. DESIGN: Cross-sectional study nested within a prospective cohort study. METHODS: Among participants in the Women's Interagency HIV Study (1331 HIV-infected women, 534 HIV-uninfected women) and Multicenter AIDS Cohort Study (600 HIV-infected men, 325 HIV-uninfected men), we measured subclinical carotid artery lesions and common carotid artery intima-media thickness using B-mode ultrasound. We estimated adjusted mean carotid artery intima-media thickness differences and prevalence ratios for carotid lesions associated with HIV-related disease and treatments, with multivariate adjustment to control for possible confounding variables. RESULTS: Among HIV-infected individuals, a low CD4+ T-cell count was independently associated with an increased prevalence of carotid lesions. Compared with the reference group of HIV-uninfected individuals, the adjusted prevalence ratio for lesions among HIV-infected individuals with CD4+ T-cell count less than 200 cells/mul was 2.00 (95% confidence interval, 1.22-3.28) in women and 1.74 (95% confidence interval, 1.04-2.93) in men. No consistent association of antiretroviral medications with carotid atherosclerosis was observed, except for a borderline significant association between protease inhibitor use and carotid lesions in men (with no association among women). History of clinical AIDS and HIV viral load were not significantly associated with carotid atherosclerosis. CONCLUSION: Beyond traditional cardiovascular disease risk factors, low CD4+ T-cell count is the most robust risk factor for increased subclinical carotid atherosclerosis in HIV-infected women and men.

Pulmonary radiological characteristics in patients with HIV infection at the time of highly active antiretroviral therapy (HAART).

OBJECTIVE: To report on radiological and epidemiological characteristics of pulmonary disease in patients with HIV infection in times of highly active antiretroviral therapy (HAART). METHODS: Clinical data of 130 HIV infected adults with acute pulmonary symptoms were compared with findings in chest radiography (n = 130) and computed tomography (CT, n = 42). Presence and distribution of consolidation, interstitial changes, pleural effusion, and adenopathy were evaluated. Results were compared to findings from sputum, bronchoalveolar lavage, transbronchial biopsy, or empirical therapy results. RESULTS: 48% of patients presented pathologic findings. Overall sensitivity for the detection of pulmonary involvement was 0.87 (chest radiography) vs. 0.97 (CT). Disease specific sensitivity was 0.33 compared to 0.70. Bacterial pneumonia (BP, n = 26, 20%) was the most frequent diagnosis, followed by pneumocystis jiroveci pneumonia (PJP, n = 17, 13%), mycobacterium avium complex (MAC, 6%), Kaposi's sarcoma and lymphoma (KS and NHL, each 4%), fungal pneumonia (2%), and tuberculosis (TBC, 1%). Focal pulmonary infiltration was predominantly present in BP (50%, n = 13). Reticular (35%; n = 6) and micronodular (35%; n = 6) infiltration were predominantly found in PJP. CONCLUSIONS: Despite HAART, lung involvement is still common. Only contrast-enhanced computed tomography shows an acceptable disease-specific sensitivity. In unclear cases, CT should be performed.