AB0671 NO EVIDENCE OF SARS-COV-2 IN THE KNEE JOINT: A CADAVER STUDY

Background:

Despite the considerable research efforts being made to learn more about COVID-19, little is known about the presence of SARS-CoV-2 genetic material in biological fluids other than respiratory droplets, blood, and feces 1,2. In particular, little is known about the presence of SARS-CoV-2 in the joints either post mortem3 or in vivo4. To the best of our knowledge, only Lopéz-Gonzalez et al.5 have published a description of acute arthritides occurring during hospitalisation due to COVID-19, and they did not find any SARS-CoV-2 genetic material in the patients’ synovial fluid samples.

Objectives:

The aim of this post mortem study was to assess the presence of SARS-CoV-2 RNA in the knee synovial fluid, synovial tissue, and bone tissue of COVID-19 patients in order to discover whether the joint is a possible route of transmission during orthopaedic surgical procedures, and clarify the possible role of SARS-CoV-2 as a directly arthritogenic virus.

Methods:

Post mortem synovial fluid, synovial tissue and bone tissue samples were collected from the knees of five patients who died of COVID-19 in our hospital between September and October 2020, and analysed for the presence of SARS-CoV-2 using a commercial real-time polymerase chain reaction (RT-PCR) panel. Quantitative RT-PCR was used to test post mortem nasopharyngeal swabs of all of the patients.

Results:

No SARS-CoV-2 RNA was detected in any of the knee samples, despite the positivity of the throat swab.

Conclusion:

Our findings indicate that SARS-CoV-2 was not detected in knee synovial fluid, synovial membrane or bone. Therefore, our results suggest that all healthcare professionals performing surgical procedures on the joints of COVID-19 patients are exposed to a risk of contagion due to exposure to respiratory droplets, blood and body fluids, but not to direct exposure to joint- or bone-related tissues. Furthermore, given that some case reports of arthritis in COVID-19 patients 5-8 show that it is possible that COVID-19 patients display viral-mediated arthralgias and arthritis, the absence of the virus in the knee highlighted by our study suggests that it is unlikely that SARS-CoV-2 has a direct inflammatory action on the joint, but it could induce an inflammation-related reaction, manifesting as a reactive arthritis 9.

References:

[1]Cheng ZJ, Shan J. 2019 Novel coronavirus: where we are and what we know. Infection. 2020;(0123456789):1-9. doi:10.1007/s15010-020-01401-y

[2]Chen Y, Chen L, Deng Q, et al. The Presence of SARS-CoV-2 RNA in Feces of COVID-19 Patients. J Med Virol. April 2020. doi:10.1002/jmv.25825

[3]Maiese A, Manetti AC, La Russa R, et al. Autopsy findings in COVID-19-related deaths: a literature review. Forensic Sci Med Pathol. 2020. doi:10.1007/s12024-020-00310-8

[4]Baldanti F, Novazzi F, Cassaniti I, Piralla A, Di A, Bruno R. Detection of the SARS-CoV-2 in different biologic specimens from positive patients with COVID-19, in Northern Italy. Authorea. 2020. doi:10.22541/au.159724509.93056098

[5]López-González M-C, Peral-Garrido ML, Calabuig I, et al. Case series of acute arthritis during COVID-19 admission. Ann Rheum Dis. 2020;0(0):annrheumdis-2020-217914. doi:10.1136/annrheumdis-2020-217914

[6]Parisi S, Borrelli R, Bianchi S, Fusaro E. Viral arthritis and COVID-19. Lancet Rheumatol. 2020;2(11):e655-e657. doi:10.1016/S2665-9913(20)30348-9

[7]Alivernini S, Cingolani A, Gessi M, et al. Comparative analysis of synovial inflammation after SARS-CoV-2 infection. Ann Rheum Dis. 2020;0(0):2-3. doi:10.1136/annrheumdis-2020-218315

[8]Talarico R, Stagnaro C, Ferro F, Carli L, Mosca M. Symmetric peripheral polyarthritis developed during SARS-CoV-2 infection. Lancet Rheumatol. 2020;2(9):e518-e519. doi:10.1016/S2665-9913(20)30216-2

[9]Di Carlo M, Tardella M, Salaffi F. Can SARS-CoV-2 induce reactive arthritis? Clin Exp Rheumatol. 2020;In press.

Acknowledgements:

We would like to thank the clinical staff of the Pathology Unit for their collaboration in performing the autopsies.

Disclosure of Interests:

None declared

Hypoalbuminemia in COVID-19: assessing the hypothesis for underlying pulmonary capillary leakage

BACKGROUND

Since the first observations of patients with COVID-19, significant hypoalbuminaemia was detected. Its causes have not been investigated yet.

OBJECTIVE

We hypothesized that pulmonary capillary leakage affects the severity of respiratory failure, causing a shift of fluids and proteins through the epithelial-endothelial barrier.

METHODS

One hundred seventy-four COVID-19 patients with respiratory symptoms, 92 admitted to the intermediate medicine ward (IMW) and 82 to the intensive care unit (ICU) at Luigi Sacco Hospital in Milan, were studied.

RESULTS

Baseline characteristics at admission were considered. Proteins, interleukin 8 (IL-8) and interleukin 10 (IL-10) in bronchoalveolar lavage fluid (BALF) were analysed in 26 ICU patients. In addition, ten autopsy ultrastructural lung studies were performed in patients with COVID-19 and compared with postmortem findings in a control group (bacterial pneumonia-ARDS and H1N1-ARDS). ICU patients had lower serum albumin than IMW patients [20 (18-23) vs 28 (24-33) g L^-1 , P < 0.001]. Serum albumin was lower in more compromised groups (lower PaO₂ -to-FiO₂ ratio and worst chest X-ray findings) and was associated with 30 days of probability of survival. Protein concentration was correlated with IL-8 and IL-10 levels in BALF. Electron microscopy examinations of eight out of ten COVID-19 lung tissues showed loosening of junctional complexes, quantitatively more pronounced than in controls, and direct viral infection of type 2 pneumocytes and endothelial cells.

CONCLUSION

Hypoalbuminaemia may serve as severity marker of epithelial-endothelial damage in patients with COVID-19. There are clues that pulmonary capillary leak syndrome plays a key role in the pathogenesis of COVID-19 and might be a potential therapeutic target.

Liver infection and COVID-19: the electron microscopy proof and revision of the literature

OBJECTIVE

COVID-19, the newly emerging infectious disease, has been associated with acute liver injury, often related to progression to severe pneumonia. The association between moderate-severe liver injury and more severe clinical course of COVID-19 has suggested that liver injury is prevalent in severe than in mild cases of COVID-19, while no difference in liver involvement has been reported between survivors and non-survivors. The spectrum of liver involvement during COVID-19 ranges from an asymptomatic elevation of liver enzymes to severe hepatitis. Only rarely, cases with acute hepatitis have been reported in the absence of respiratory symptoms. Both epithelial and biliary cells possess the angiotensin-converting enzyme-2 receptors that SARS-CoV-2 uses to be internalized. However, to our knowledge, no ultrastructural identification of the virus in liver cells has been reported to date. Here we provide evidence of SARS-CoV-2 in the liver of two patients, a 34-year-old woman and a 60-year-old man with COVID-19.

PATIENTS AND METHODS

We investigated two patients with COVID-19 showing several virions within cytoplasmic vacuoles of cholangiocytes and in endothelial cells of hepatic sinusoids. In both patients, we performed histological and ultrastructural examinations by liver biopsy. After two months, both patients were free of symptoms, and the SARS-CoV-2 infection had resolved.

RESULTS

Liver biopsy histological and ultrastructural examination showed liver injury and several virions within cytoplasmic vacuoles of cholangiocytes and in endothelial cells of hepatic sinusoids.

CONCLUSIONS

Although most studies in COVID-19 have been focused on the lungs, recently, cholestatic liver pathology has been introduced in the spectrum of pathological changes related to COVID-19. To the best of our knowledge, those presented in this paper are the first images of hepatic SARS-CoV-2 infected liver cells. Our findings suggest a role for cholangiocytes and biliary structures in the COVID-19.

Abstract P6-12-17: H-ferritin allows nanometronomic treatment of breast cancer with doxorubicin preventing drug resistance and circumventing cardiotoxicity

Chemotherapeutic treatment of breast cancer is based on maximum tolerated dose (MTD) approach.1 However, advanced stage tumors are not effectively eradicated by MTD owing to suboptimal drug targeting, onset of therapeutic resistance and neoangiogenesis. In contrast, “metronomic” chemotherapy is based on frequent drug administrationsat lower doses, resulting in neovascularization inhibition and induction of tumor dormancy.1,2 However, several limiting factors remain for LDM in order to displace MTD treatments in clinical practice, including 1) low drug accumulation at tumor site,2 2) controversial effectiveness against chemoresistance in advanced metastatic cancers, and 3) acquired resistance after prolonged treatment. Recent advances in nanotechnology could offer groundbreaking solutions to improve the effectiveness of LDM chemotherapy, by taking advantage of the unique targeting efficiency of engineered nanocarriers.3 Here, we propose a new concept of “nanometronomic” chemotherapy, exploiting the H-ferritin (HFn)-mediated targeted delivery of doxorubicin (DOX)in an aggressive and metastatic breast cancer mouse model with DOX-inducible chemoresistance. HFn nanocages naturally target cancer cells4 owing to its affinity for transferrin receptor 1. HFn-DOX was recently demonstrated to overcome chemoresistance by actively promoting DOX nuclear translocation in vitro5,6 and was tested as a MTD treatment on a DOX-sensitive tumor model with encouraging results.7 We find that LDM administration of HFn-DOX strongly improves the antitumor potential of DOX chemotherapy arresting the tumor progression. Indeed, in vitro and in vivo results demonstrate that HFn nanocages mediate the nuclear delivery of DOX and increase DOX accumulation both in tumor tissue and in cancer cell nuclei, resulting in increased efficacy. Moreover, we find that HFn-DOX antitumor effect is attributable to multiple nanodrug actions beyond cell killing, including inhibition of tumor angiogenesis and avoidance of chemoresistance. Otherwise, although an even better reduction of tumor progression was achieved with liposomal DOX (pl-DOX) a five-fold increase in MDR-1-positive cells has been displayed, suggesting that liposomal DOX is not suitable in view of a protracted metronomic treatment, due to the onset of chemoresistance. Multiparametric assessment of heart tissues, including histology, ultrastructural analysis of tissue morphology, and measurement of markers of reactive oxygen species and hepatic/renal conditions, provided evidence that metronomic HFn-DOX allowed us to overcome cardiotoxicity contrary to what is observed with DOX and pl-DOX. Our results suggest that HFn-DOX has tremendous potential for the development of “nanometronomic” chemotherapy toward safe and tailored oncological treatments.

1. Kareva I, et al. Cancer Lett 2015; 358: 100.

2. Kerbel RS. Cancer Res Treat 2007; 39: 150.

3. Cruz-Munoz W, et al. Angiogenesis 2014; 7: 661.

4. Corsi F, Mazzucchelli S. Ther Deliv. 2016; 7: 149.

5. Bellini M, et al.. J Controlled Rel 2014;196: 184.

6. Zhang L, et al. Adv. Healthcare Mat. 2015; 4: 1305.

7. Liang M, et al. Proc Natl Acad Sci USA 2014; 111: 14900.

Citation Format: Mazzucchelli S, Fiandra L, Bellini M, Truffi M, Rizzuto MA, Sorrentino L, Longhi E, Nebuloni M, Prosperi D, Corsi F. H-ferritin allows nanometronomic treatment of breast cancer with doxorubicin preventing drug resistance and circumventing cardiotoxicity [abstract]. In: Proceedings of the Thirty-Ninth Annual CTRC-AACR San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-12-17.

PTX3 as a potential endothelial dysfunction biomarker for severity of preeclampsia and IUGR

Endothelial dysfunction typical of preeclampsia (PE) is the result of an excessive maternal inflammatory response to pregnancy. We investigated PTX3 in maternal, fetal and placental compartments in complicated pregnancies. Maternal blood samples were collected during the third trimester in 53 PE, 43 IUGR (intrauterine growth restriction) and 50 normal pregnancies. Fetal samples were collected from the umbilical vein in 26 PE, 23 IUGR and 26 normal pregnancies at elective cesarean section. Pattern and site of expression of PTX3 were studied by immunohistochemistry (IHC) on placenta, decidual bed and maternal peritoneum. PE and IUGR pregnancies had significantly higher maternal PTX3 levels compared to normal pregnancies, with IUGR significantly lower than PE. Maternal peritoneum expressed a significantly higher signal in the endothelium of pathological compared to normal pregnancies. The maternal increase of PTX3 correlated with the severity of disease with higher PTX3 concentrations in severe PE. Increased PTX3 levels in PE and IUGR mothers, together with IHC data represent the expression of altered endothelial function on the maternal side. IUGR fetuses had higher PTX3 values than controls and the increase was related to IUGR severity, likely reflecting the hypoxic environment. These data confirm the relevance of PTX3 in support the hypothesis that PE is a disease associated with altered maternal endothelial function. The PTX3 increase in IUGR fetuses deserves further investigation.

Inflammatory reaction and implantation: the new entries PTX3 and D6

Successful embryonic implantation implies anchoring the conceptus in the maternal uterine wall, establishing a vascular supply to enable optimal growth and development of the conceptus, and promoting tolerance of fetal alloantigens encoded by paternal genes. To achieve these goals, complex molecular dialogues take place among the maternal endometrium, the conceptus, and the placenta. Several factors are involved in the fetal-maternal interaction, including hormones, growth factors, cytokines, chemokines, adhesion molecules, extracellular matrix components, and matrix-degrading enzymes. This complex cross-talk results in the induction of a local inflammatory response and a state of systemic inflammation, as revealed by leukocytosis, endothelium activation, increased activity of innate immune cells, and increased levels of inflammatory cytokines and chemokines. The enriched cytokine milieu associated to implantation is likely to control trophoblast migration and differentiation, leukocyte influx and activation, complement activation, as well as angiogenic and angiostatic processes in the implantation site. Finally, these mediators play a key role in tuning the immune responses to protect the fetus from infections as well as from maternal rejection. Here, the role of pro-inflammatory networks activated in implantation will be discussed. In particular, emphasis will be put on two new players involved in regulating inflammation at the maternal-fetal interface: the long pentraxin PTX3 and the decoy receptor for inflammatory chemokines D6.

[Vacuum-assisted breast biopsy for diagnosis of non-palpable lesions: experience with 226 cases]

Vacuum-assisted breast biopsy (VABB) is now available for non-palpable lesions. The present study describes the results obtained from 226 consecutive VABBs performed at "L. Sacco" Hospital, Milan, from November 2005 to July 2007 (198 stereotactic and 28 ultrasonographic procedures). Adequate tissue samples for histopathological evaluation were obtained in 225 cases (99.6%). The diagnoses were as follows: 9 normal tissues (4%), 97 benign (43%), 25 "probably benign" (11%), 4 "suspicious for malignancy" (2%) and 90 malignant (40%, 53 in situ and 37 infiltrating carcinoma). Of the 90 malignant cases, 38 (42.2%) underwent subsequent surgical excision in our Unit; 84.2% (32/38) had concordant histopathological findings. In conclusion, VABB is an accurate and safe technique for diagnosis of non-palpable lesions, and in experienced hands avoids unnecessary surgical procedures.

Challenging diagnosis of an unusual solitary pulmonary nodule

We describe the case of a 64-year-old woman with a solitary pulmonary nodule and a previous breast carcinoma whose diagnosis of histoplasmoma was established only after surgical resection and appropriate stains. It is important not to confuse these two diseases as this will prevent inappropriate medical treatment. Limited surgery is indicated for the treatment of these circumscribed lesions.

Ghrelin in human medullary thyroid carcinomas

OBJECTIVE

Ghrelin is a novel gastrointestinal hormone involved in several metabolic functions. It has been identified previously in several normal and tumoral neuroendocrine tissues, including human medullary thyroid carcinomas (MTCs). The aim of the study was to evaluate ghrelin levels in patients with MTC and nontoxic goitre (NTG) with elevated calcitonin (CT) levels, as an additional marker of the disease.

PATIENTS AND DESIGN

The study included 22 patients with MTC (four before and 18 after thyroidectomy), 12 patients with NTG with basal CT levels exceeding 10 ng/l and 15 healthy subjects matched for age, sex and body mass index (BMI). After thyroidectomy, MTC patients were considered cured when basal and pentagastrin-stimulated CT levels were < 0.2 and < 10 ng/l, respectively. A pentagastrin-induced CT peak over 50 ng/l was considered as an abnormal response while 100 ng/l was the cut-off accepted for the diagnosis of C-cell hyperplasia or tumour. Circulating ghrelin and CT levels were evaluated at baseline in patients and controls and at -10, 0, 1, 2, 5 and 15 min after pentagastrin injection (0.5 microg/kg body weight) in 12 patients with MTC and nine with NTG. Four surgically removed MTCs were tested for ghrelin expression.

MEASUREMENTS

Total plasma ghrelin and CT levels were measured with a commercially available radioimmunoassay (RIA) and two-site chemiluminescence immunometric assays, respectively. In paraffin-embedded MTC samples ghrelin immunostaining was performed with a polyclonal antibody (1:1000) and the reaction visualized by an indirect immunoperoxidase system.

RESULTS

Plasma ghrelin levels found in cured or not cured MTC and in NTG patients were similar to those of BMI-matched healthy controls. No correlation between ghrelin and CT levels, thyroid disease or previous thyroidectomy was observed. The administration of pentagastrin caused a 17% increase in ghrelin levels (basal ghrelin vs. peak: 162 +/- 62 pmol/l vs. 189 +/- 58 pmol/l, P < 0.05) that was particularly evident (33% increase) in patients with an abnormal CT response to the test (CT > 50 ng/l). Immunohistochemistry showed positivity for ghrelin in a small proportion of CT positive cells from the four MTCs removed.

CONCLUSIONS

Patients with MTC, NTG and controls showed similar ghrelin levels, ruling out this parameter as a marker of MTC. The increase in ghrelin levels in patients with a positive CT response to pentagastrin, together with the immunopositivity for ghrelin in some MTC cells, suggests C cells as minor source of ghrelin production.

Ultrastructural study of renal involvement in two females with Anderson-Fabry disease

Anderson-Fabry disease (AFD) is a rare X-linked lipid storage disorder due to a deficient lysosomal a-galactosidase A (a-Gal) activity. In males with the classic form of the disease the enzymatic defect leads to progressive accumulation of glycosphingolipids (GL) in different organs, mainly in the kidney, heart, and brain, causing severe multisystem failure. AFD is usually mild in heterozygous females, but severe cerebrovascular, renal, and cardiac manifestations have been rarely described. The aim of this study is to describe renal involvement of mild symptomatic female carriers by ultrastructural analysis focusing to microvascular lesions, considered to be one of the major causes of systemic disease in AFD. Resin-embedded renal biopsies from 2 sisters with isolated mild proteinuria and belonging to a family group with AFD were observed by light and electron microscopy. In spite of the mild clinical symptoms, diffuse GL storages were demonstrated in all types of glomerular cells and in interstitial endothelial cells. Moreover, platelets were frequently observed in glomerular vassels, a feature coherent with a possible role of prothrombotic state, and platelet activation, in early glomerular lesions.

Evolution of renal pathology in Fabry disease

Fabry disease is a rare lysosomal storage disorder which results from deficient activity of the enzyme alpha-galactosidase A. The resultant deposition and progressive accumulation of glycosphingolipids in all types of body tissue leads to severe clinical manifestations involving the heart, CNS and kidney. Renal manifestations are observed relatively early in the course of the disease, and progression to end-stage renal failure is common in hemizygous males in the third to fifth decades of life. Renal biopsy specimens reveal evidence of diffuse intracytoplasmic glycosphingolipid accumulation, mainly affecting podocytes and epithelial cells of distal tubules, which are strikingly enlarged and vacuolated. On electron microscopy the deposits appear as typical osmiophilic inclusion bodies in the cytoplasm of all kinds of renal cells, and show a characteristic 'onion skin' or 'zebra' appearance. These pathological features are also evident in heterozygous females. Deposits occur before the development of renal impairment. As patients age, the disease progresses in cells throughout the kidney, and is associated with increasing glycosphingolipid accumulation.

CONCLUSION

The age-related evolution of renal pathology in Fabry disease is closely correlated with progressive intracellular deposition of glycosphingolipid and ultimately leads to end-stage renal failure.

Clinical aspects of the AIDS dementia complex in relation to histopathological and immunohistochemical variables

To correlate cerebral histopathological and immunohistochemical changes in the neuroclinical features of the AIDS dementia complex (ADC), autopsy results of 28 ADC patients were related, in a retrospective analysis, to scores on a standardised neurological examination performed at neurologic onset. From a histopathological point of view, the cases were classified as follows: 9 cases of HIV leucoencephalopathy (HIVL; diffuse myelin damage and rare microglial nodules), 7 cases of HIV encephalitis (HIVE; several microglial nodules and no myelin damage) and 12 cases of mixed HIVL and HIVE (HIVL-E). The groups differed significantly with respect to symptoms and CD4 count at neurologic onset, survival and neurological impairment. Immunohistochemically, the interstitial component (p24-positive cells scattered singly within the white matter) was significantly more prevalent in HIVL, and the micronodular component (p24-positive cells confined within microglial nodules) in HIVE. Neurological damage was worse in cases with a high prevalence of interstitial component or a low prevalence of micronodular component. HIVE, HIVL and HIVL-E are distinct clinical forms of ADC. Neurological impairment is related to white matter damage.

Molecular characterization and sequence analysis of polyomavirus strains isolated from needle biopsy specimens of kidney allograft recipients

We retrospectively examined 29 renal allograft biopsy specimens from 42 kidney transplant recipients by means of molecular biologic techniques (nested polymerase chain reaction), immunohistochemical analysis (anti-SV40 antibody), and histologic examination to evaluate the presence of polyomaviruses (PVs), viral genotypes, genomic mutations, and their pathologic significance. PV genomes were found in six cases (21%); restriction fragment length polymorphism analysis characterized 4 as JC virus (JCV) and 2 as BK virus (BKV). The latter also were positively stained immunohistochemically and showed histologically typical intranuclear viral inclusions; JCV cases were negative. DNA sequence analysis revealed only minor changes in the 4 JCV cases (3 archetypes and 1 JCV type 3, not associated with a known pathogenic genotype) but identified 2 specific variants in the BKV isolates (AS and WW strains). Given the different histologic findings (mixed inflammatory infiltration in the AS and no inflammation in the WW strain), we speculate that different BKV strains may cause differential damage in transplanted kidneys. Finally, the negative histologic and immunohistochemical JCV results, as well as the absence of viral mutations, indicate that JCV renal infection is latent in transplant recipients.

Molecular characterization and sequence analysis of polyomavirus strains isolated from needle biopsy specimens of kidney allograft recipients

We retrospectively examined 29 renal allograft biopsy specimens from 42 kidney transplant recipients by means of molecular biologic techniques (nested polymerase chain reaction), immunohistochemical analysis (anti-SV40 antibody), and histologic examination to evaluate the presence of polyomaviruses (PVs), viral genotypes, genomic mutations, and their pathologic significance. PV genomes were found in six cases (21%); restriction fragment length polymorphism analysis characterized 4 as JC virus (JCV) and 2 as BK virus (BKV). The latter also were positively stained immunohistochemically and showed histologically typical intranuclear viral inclusions; JCV cases were negative. DNA sequence analysis revealed only minor changes in the 4 JCV cases (3 archetypes and 1 JCV type 3, not associated with a known pathogenic genotype) but identified 2 specific variants in the BKV isolates (AS and WW strains). Given the different histologic findings (mixed inflammatory infiltration in the AS and no inflammation in the WW strain), we speculate that different BKV strains may cause differential damage in transplanted kidneys. Finally, the negative histologic and immunohistochemical JCV results, as well as the absence of viral mutations, indicate that JCV renal infection is latent in transplant recipients.

Cryptococcus neoformans infection in a cohort of Italian AIDS patients: natural history, early prognostic parameters, and autopsy findings

This observational cohort study of 4,160 AIDS patients hospitalised in a single institution in northern Italy between January 1985 and December 1999 was carried out in order to assess the natural history of cryptococcosis, the epidemiological trend of this opportunistic infection, the risk factors predictive of death at 10 weeks, the response to therapy, and autopsy findings. Cryptococcosis was diagnosed in 177 (4.2%) patients and was the AIDS-defining disease in 2.8% of cases. Its prevalence decreased significantly over time (from 6.4% in the period 1985-1989 to 5.7% in 1990-1993, 3.1% in 1994-1996, and 1.9% in 1997-1999, P <0.0001). Although neurologic disease was the most frequent clinical picture, a significant proportion of the patients (24.2%) presented with extraneural cryptococcosis. In a Cox multivariate analysis, high titres of cerebrospinal fluid antigen (>5000) and drug addiction were predictive of death at 10 weeks. A complete clinical and mycological response was achieved in 60.8% of the treated patients, with the highest response rate being observed in those treated with amphotericin plus flucytosine (66.6%). Cryptococcosis relapsed in 12.8% of patients on secondary prophylaxis. Autopsy findings demonstrated that cryptococcosis is a disseminated disease, but long-term antifungal treatment may be able to eradicate it in a subgroup of patients.

Rantes distribution and cellular localization in the brain of HIV-infected patients

OBJECTIVE

To study the immunochemical distribution ofRantes chemokine and its correlation with HIV-p24 expression, in brains with HIV-related lesions.

MATERIAL AND METHODS

17 HIV-positive cases of HIV-related brain lesions, 7 HIV-positive cases without cerebral HIV-related lesions (5 with opportunistic brain diseases), and 7 HIV-negative cases as controls (4 with brain lesion) were selected.

RESULTS

High expression of Rantes was observed in the cases with inflammatory brain lesions (22/24 HIV-positive and 2/7 HIV-negative patients). Positivity was observed in the diffuse and nodular microglial cells and lymphocytes. In the patients with HIV-related lesions, the presence of Rantes-stained microglia did not correlate with that of HIV-p24-positive cells. Positive astrocytes were only found in the HIV-positive patients. Multinucleated giant cells were always Rantes-negative.

CONCLUSIONS

Our results seem to demonstrate the role of Rantes chemokine in inducing inflammatory brain perivascular and microglial reactions both in HIV-positive and -negative patients.

Beta amyloid precursor protein and patterns of HIV p24 immunohistochemistry in different brain areas of AIDS patients

OBJECTIVES

To evaluate the correlation between immunohistochemical positive patterns (globular and filamentous structures) of beta-amyloid precursor protein (beta-APP), used as a marker of axonal damage, and the different distribution of HIV p24 antigens, in three different brain areas of AIDS patients.

METHODS

Eighteen AIDS patients with HIV-related brain lesions were included in the study. Forty-nine sections from basal ganglia, frontal cortex and hippocampus were selected. After microwave oven pre-treatment, the sections were incubated with anti-HIV p24 and anti-beta-APP monoclonal antibodies; the reactions were developed with peroxidase/3,3'diaminobenzidine. The positivity was graded by semi-quantitative scores. Double immunohistochemical staining was used to evaluate the co-localization of the antigens.

RESULTS

HIV p24 immunohistochemistry was positive in 44 of 49 sections (89%), with a prevalence of interstitial positive cells and positive microglial nodules in 27 and 13 sections respectively. beta-APP-positive structures were demonstrated in 23 of 44 sections (52%) with HIV-related lesions, and were absent from the five sections without viral expression. Globular and filamentous lesions were observed in 21 of 23 sections and 10 of 23 lesions respectively. Moreover, a high grade of globular type lesion was related to an elevated presence of diffuse interstitial HIV p24-positive cells in basal ganglia; double immunohistochemical reactions demonstrated the co-localization of beta-APP globules and HIV p24 antigens.

CONCLUSIONS

The data obtained confirm the coexpression of beta-APP and viral antigens in particular areas of the brain with HIV-related lesions; there is a strict correlation between beta-APP globules (indicating chronic cerebral damage) and the interstitial pattern of HIV p24 immunohistochemistry.

Anaerobic accumulation of amino acids in rice roots: role of the glutamine synthetase/glutamate synthase cycle

Accumulation of amino acids was studied in rice roots of 3-day-old seedlings subjected for 48h to anaerobic conditions. Alanine and Gaba were the main amino acids accumulated under anoxia. Their synthesis was strongly inhibited by MSX and AZA, inhibitors of glutamine synthetase and glutamate synthase. These activities increased after 8h of anaerobic treatment and, by immunoprecipitation of 35S-labeled proteins, it was shown that glutamine synthetase and ferredoxin-dependent glutamate synthase were synthesized during the treatment. These findings indicate that the glutamine synthetase/glutamate synthase cycle play an important role in anaerobic amino acid accumulation.

Extracellular Matrix Globules in Renal Oncocytoma

Extracellular hyaline globules resulting from abnormal accumulation of matrix components have been described in several pathological conditions, including renal tumors. We studied 16 renal oncocytomas and observed these bodies in 11 of them. In these tumors, they showed a homogeneous texture as well as roundish, smooth contours, and were easily detected in hematoxylin-eosin sections in five cases. PAS staining greatly facilitated the identification of globules in the remaining six cases, where they were fewer in number. Immunohistochemically, they appeared to be composed primarily of basement membrane material, being strongly reactive to antibodies for type IV collagen, laminin, and heparan sulphate proteoglycan. In addition, a weak immunoreactivity for type I and type III collagen, and fibronectin was observed in some cases, whereas no globule stained for tenascin. We also analyzed 89 renal cell carcinomas, and found somewhat similar bodies in 10 of them. However, they were more scanty in the latter tumors, and displayed a more irregular configuration with granular or smudged contours. We conclude that, although the mere presence of extracellular hyaline globules does not justify a distinction between renal oncocytoma and renal cell carcinoma, the detection of a large number of well-demarcated, roundish extracellular bodies with smooth contours suggests renal oncocytoma.

Renal pathological changes in Fabry disease

Fabry disease is a rare X-linked disorder, characterized by deficient activity of the lysosomal enzyme alpha-galactosidase A. This leads to systemic accumulation of the glycosphingolipid globotriaosylceramide (Gb3) in all body tissues and organs, including the kidney. Renal manifestations are less evident in female heterozygotes than in male hemizygotes, according to the Lyon hypothesis. Accumulation of Gb3 occurs mainly in the epithelial cells of Henle's loop and distal tubule, inducing early impairment in renal concentrating ability; involvement of the proximal tubule induces Fanconi syndrome. All types of glomerular cells are involved, especially podocytes, and glomerular proteinuria may occur at a young age. The evolution of renal Fabry disease is characterized by progressive deterioration of renal function to end-stage renal failure (ESRF). Ultrastructural study of kidney biopsies reveals typical bodies in the cytoplasm of all types of renal cells, characterized by concentric lamellation of clear and dark layers with a periodicity of 35-50 A. Management of progressive renal disease requires dietetic and therapeutic strategies, usually indicated in developing chronic renal failure, with dialysis and renal transplantation required for patients with ESRF. The recent development of enzyme replacement therapy, however, should make it possible to prevent or reverse the progressive renal dysfunction associated with Fabry disease.

Cytologic and biomolecular diagnosis of polyomavirus infection in urine specimens of HIV-positive patients

OBJECTIVE

To evaluate the frequency of human polyomavirus reactivation in urine specimens from HIV-positive patients; compare the sensitivity of cytology, immunohistochemistry and molecular biology; differentiate viral genotypes; and correlate the results with urinary cytologic abnormalities.

STUDY DESIGN

Urine specimens from 78 unselected HIV-positive patients were evaluated by means of cytology, immunohistochemistry and nested polymerase chain reaction (n-PCR) to evaluate the presence of polyomaviruses. Restriction fragment length polymorphism (RFLP) was carried out in positive cases in order to differentiate BK virus (BKV) from JC virus (JCV). CD4 cells and serum creatinine levels were evaluated as indices of immune status and renal function, respectively, whereas the presence of red blood cells was used as an index of urogenital damage.

RESULTS

Cytologic evidence of polyomavirus infection was found in 17 samples and immunohistochemically confirmed in 9; another 6 cytologically negative cases were detected by means of immunohistochemistry. In all cases, only one or two cells showed typical viral inclusions or positive staining. n-PCR identified 44 positive samples, thus confirming all of the cytologically and immunohistochemically positive cases and detecting polyomavirus genome in a further 21. RFLP detected 39 JCV, 1 BKV and 4 JCV-BKV infections. No correlation was found between the presence or type of polyomavirus and immune status, but red blood cells were found more frequently in the positive than in the negative samples. Serum creatinine levels fell within the normal range in all cases.

CONCLUSION

Molecular biology is the most sensitive tool for detecting polyomavirus urinary infection in HIV-positive patients and the only reliable method of differentiating JCV and BKV viral genotypes.

Etiology of microglial nodules in brains of patients with acquired immunodeficiency syndrome

Microglial nodules associated with opportunistic and HIV-related lesions are frequently found in the brains of AIDS patients. However, in many cases, the causative agent is only presumptively suspected. We reviewed 199 brains of AIDS patients with micronodular lesions to clarify their etiology by immunohistochemistry (to Toxoplasma gondii, cytomegalovirus, herpes simplex virus I/II, varicella zoster virus and HIV-p24 core protein), PCR (for herpetic viruses and Mycobacterium tuberculosis) and electron microscopy. Productive HIV infection was observed in 110 cases (55.1%): 30 cases with Toxoplasma gondii encephalitis, 30 with cytomegalovirus encephalitis, eight with multiple cerebral diseases, while in the remaining 42 cases HIV was the only pathogenetic agent. Multinucleated giant cells (hallmark of HIV infection) were found in the MGNs of 85/110 cases with HIV-related lesions; the remaining 25 cases had only p24 positive cells but no multinucleated giant cells. In these latter cases the micronodular lesions had been initially attributed to the main opportunistic agent found in the brain, or defined as subacute encephalitis. Individual microglial nodules positive for an opportunistic pathogen were generally negative for HIV antigens. In 13 cases no opportunistic agent or HIV productive infection was found. In these cases, PCR and electron microscopy examination for HIV and other viral infections were negative. Our data suggest that HIV-immunohistochemistry should be used for the etiological diagnosis of micronodular lesions in AIDS brains, even in the presence of other pathogens. After extensive search, the etiology of the microglial nodules remains unknown in only a small percentage of cases.

BK virus renal infection in a patient with the acquired immunodeficiency syndrome

BACKGROUND

We describe herein a patient with the acquired immunodeficiency syndrome and renal failure due to biopsy-proven BK virus (BKV) infection. Three months after the diagnosis of the renal viral infection, his condition remained unchanged. Although BKV has previously been shown to be associated with ureteral stenosis and renal damage in renal transplant patients, to our knowledge, the literature contains only 3 cases describing the presence of BKV lesions in the kidneys of immunosuppressed patients who had not undergone transplantation.

METHODS

The presence of BKV infection was demonstrated by means of histology, immunohistochemistry with polyclonal anti-SV40 antibody, immunoelectron microscopy, polymerase chain reaction, and enzymatic cleavage with BamHI.

RESULTS

Histologic examination revealed interstitial inflammatory infiltrates and tubules with enlarged and eosinophilic nuclei.

CONCLUSIONS

The high frequency of latent BKV infection and its reactivation during immunosuppression suggest that the possibility of its involvement in renal damage should be considered in immunocompromised patients.

Hepatic metastases from medullary thyroid carcinoma appearing twelve years after the eradication of primitive tumor: cytological and radiological aspects

We report on radiological and cytological findings from a case of medullary thyroid carcinoma (MTC) metastatizing to the liver 12 yr after the eradication of the primary neoplasm. This behavior has never before been described in a sporadic form of MTC.

Use of magnetic beads for tissue DNA extraction and IS6110 Mycobacterium tuberculosis PCR

Polymerase chain reaction (PCR) techniques are used increasingly for the diagnosis of Mycobacterium tuberculosis infection and can be used on the DNA obtained from both frozen and formalin fixed, paraffin wax embedded tissues. However, the extraction of DNA by means of the conventional phenol/chloroform method is time consuming and requires the use of potentially dangerous chemical reagents. This paper describes a method based upon the use of magnetic beads for the extraction of M tuberculosis DNA from both routinely formalin fixed, paraffin wax embedded tissues and frozen tissues. Magnetic bead extracted DNA from brain, lymph node, and lung tissues collected from patients with human immunodeficiency virus and tuberculosis was compared with that extracted using the phenol/chloroform method. The magnetic bead extraction procedure requires less than two hours, including the time necessary to dewax the tissue sections. In all cases, the DNA extracted with both methods was amplified successfully by PCR for the M tuberculosis IS6110 sequence. Magnetic bead DNA extraction can be used on both frozen and archival tissues: the method is reliable, simple, sensitive, and rapid; in addition, it does not use hazardous procedures or specialised laboratory equipment and can be used for routine DNA isolation from various human tissues.

Detection and typing of JC virus in autopsy brains and extraneural organs of AIDS patients and non-immunocompromised individuals

The distribution of JC virus (JCV) variants in the brain, lung, liver, kidney, spleen and lymph nodes collected at autopsy from AIDS patients with (Group A: 10 Ss) and without (Group B: 5 Ss) progressive multifocal leukoencephalopathy (PML) and from HIV-negative patients (Group C: 5 Ss), was examined by amplifying the JCV large T antigen (LT), the regulatory (R) and the VP1 regions. Among the samples from the PML patients, JCV DNA was detected in all of the demyelinating areas, in 60% of the lesion-free brain tissues, in 60% of the lung tissues and in 40% of the spleen and kidney tissues, whereas all liver and lymph node sections were negative. JCV DNA was also found in two of the five brain specimens, in two of the five kidney specimens, in one of the five lung specimens from the HIV-positive patients without PML and in the brain specimens from two of the five HIV-negative subjects. Nucleotide sequence analysis indicated that all of the R region amplified from extraneural tissues had rearrangements similar to those of the Mad-4 strain and that VP1-region amplified products were similar to the Mad-1 strain. In the brain specimens from two PML patients, we found a unique rearranged R region, along with a VP1 region of JCV type 2. In addition, an almost unique variant with multiple rearrangements in the R region and unusual base mutations in the VP1 region was detected in the brain sample from another PML patient. The data indicate that diffuse visceral involvement of JCV is particularly frequent in AIDS patients with PML. Moreover, the presence of rearrangements and mutations, involving different regions of the viral genome, observed in PML-affected brain tissues, could represent a risk factor for the development of PML in immunosuppressed individuals.

VZV fulminant necrotizing encephalitis with concomitant EBV-related lymphoma and CMV ventriculitis: report of an AIDS case

A case of AIDS with varicella zoster virus fulminant necrotizing encephalitis associated with cytomegalovirus ependymitis-subependymitis and a periventricular Epstein-Barr virus-related lymphoma is described. The patient had no herpes zoster cutaneous eruptions and died three days after the onset of symptoms. Varicella zoster virus and cytomegalovirus antigens were found by immunohistochemistry in the same area around a necrotic periventricular lesion; a periventricular lymphoma, large B cell type, was also observed. In situ hybridization with Epstein-Barr virus-encoded- RNAs probe was positive in about 40% of the neoplastic cells. The association of herpes-related lesions in the same cerebral region should be consistent in AIDS cases with acute neurological symptoms.

Comprehensive study on structure-activity relationships of rifamycins: discussion of molecular and crystal structure and spectroscopic and thermochemical properties of rifamycin O

The mechanism of action of rifamycins against bacterial DNA-dependent RNA polymerase has been explained on the basis of the spatial arrangement of four oxygens which can form hydrogen bonds with the enzyme. Structural descriptors are derived from X-ray diffraction crystal structures of 25 active and nonactive rifamycins. Principal component analysis is used to find the combination of structural parameters which better discriminate between active and nonactive rifamycins. Two possible mechanisms of molecular rearrangement are described which can convert nonactive into active conformations. The energy involved for conformational rearrangements is studied by molecular modeling techniques. Methyl C34 is found to play a key role for determining the geometry of the pharmacophore. Rifamycin O, reported to be active, is obtained by oxidation of rifamycin B and is studied by X-ray single-crystal diffractometry, by solution IR and NMR spectroscopy, and by thermal analysis. Surprisingly the oxidation process is totally stereospecific, and an explanation is given based on solution spectroscopic evidence. The conformation found in the solid state is typical of nonactive compounds, and molecular mechanics calculations show that a molecular rearrangement to the active conformation would require about 15 kcal/mol. Thermal analysis confirms that rifamycin O has a sterically constrained conformation. Therefore, it is likely that the antibiotic activity of rifamycin O is due either to chemical modification prior to reaching the enzyme or to conformational activation.

Renal Encephalitozoon (Septata) intestinalis infection in a patient with AIDS. Post-mortem identification by means of transmission electron microscopy and PCR

We describe the occurrence of renal Encephalitozoon (Septata) intestinalis infection in a 35-year-old AIDS patient who died with disseminated tuberculosis. The patient did not complain of specific symptoms involving the kidney or lower urinary tract during life, but at autopsy, light microscopic examination of the kidney revealed numerous small round or oval bodies in the tubules and tubular cell cytoplasm that were interpreted as intracellular protozoa. Transmission electron microscopy of tissue retrieved from paraffin-embedded samples identified these organisms as microsporidia belonging to the Encephalitozoonidae family, but did not allow definitive identification of the species of infecting parasite. This was made possible only by means of Southern blot hybridization after the polymerase chain reaction, which recognized the micro-organism as E. intestinalis.

Evaluation of PCR in detection of Mycobacterium tuberculosis from formalin-fixed, paraffin-embedded tissues: comparison of four amplification assays

We compared the sensitivities and specificities of four nested PCR assays for the detection of Mycobacterium tuberculosis from formalin-fixed, paraffin-embedded tissues. Thirty-seven autopsy samples from human immunodeficiency virus-positive patients were analyzed: 15 were M. tuberculosis positive, 11 served as negative controls, and 11 were Ziehl-Neelsen positive without cultural confirmation of M. tuberculosis. Three genomic sequences (mtp40, 65-kDa antigen gene, and IS6110) with different molecular masses and numbers of repetitions within the M. tuberculosis genome were targeted. On the IS6110 sequence, two fragments of different sizes (106 and 123 bp, respectively) were amplified with two separate pairs of primers. The highest sensitivity rates were obtained by amplifying the highly repetitive IS6110 insertion sequence, and the different primers tested showed a sensitivity ranging from 80 to 87%. Amplification of the large 223-bp fragment of the mtp40 sequence present in a single copy in the M. tuberculosis genome yielded a high rate of false-negative results, ranging from 66 to 80%. A poor sensitivity (from 47 to 60%) was also shown by PCR amplification of the 142-bp 65-kDa antigen gene. All the PCRs except that for the 65-kDa antigen gene showed a specificity of 100%. Moreover, different results were obtained with different dilutions of DNA, and DNA concentrations of 1 and 3 microg yielded the highest sensitivities depending upon which protocol was used. Application of the PCRs to the Ziehl-Neelsen-positive, culture-negative samples confirmed the sensitivities of the PCRs obtained with the control samples. In conclusion, PCR can successfully be used to detect M. tuberculosis from paraffin-embedded tissues and can be particularly useful in the validation of a diagnosis of tuberculosis in clinical settings in which the diagnosis is uncertain. However, the efficacy of PCR strictly depends on several amplification parameters such as DNA concentration, target DNA size, and the repetitiveness of the amplified sequence.

Nested polymerase chain reaction for Mycobacterium tuberculosis IS6110 sequence on formalin-fixed paraffin-embedded tissues with granulomatous diseases for rapid diagnosis of tuberculosis

We evaluated the sensitivity and specificity of a nested polymerase chain reaction (PCR) to the Mycobacterium tuberculosis IS6110 sequence on formalin-fixed paraffin-embedded tissue samples from patients with tubercular and other granulomatous lesions. Five groups of patients and samples were studied: (1) 28 samples from HIV-positive patients with tuberculosis, (2) 8 samples from HIV-negative patients with histologically suspected tuberculosis (confirmed by culture in 5 cases), (3) lymph nodes from 5 HIV-positive patients with Mycobacterium avium-intracellulare infection, (4) lymph nodes from 30 patients with sarcoidosis, and (5) specimens from 17 patients with other granulomatous diseases. The DNA was extracted from sections with a total thickness of 60 microm, and PCR amplified an internal fragment of 123 base pairs. All of the cases with M. tuberculosis infection were PCR-positive, although this sensitivity was partially related to the initial concentration of the DNA used for amplification. Two of the group 4 samples also were repeatedly positive, thus reducing the specificity of the method. All of the cases with granulomatous diseases other than sarcoidosis were negative. We propose a simplified and highly sensitive nested PCR for the diagnosis of M. tuberculosis infection on archived material in HIV-positive and HIV-negative patients.

Hepatic histology of patients with HIV infection and chronic hepatitis C treated with interferon

AIMS

To evaluate the histological changes seen in liver biopsies after interferon (IFN) treatment in patients with chronic hepatitis C and human immunodeficiency virus (HIV) infection.

METHODS

Twenty four intravenous drug users with chronic hepatitis C were investigated histologically before beginning a 12 month course of IFN treatment and 18 months later. Twelve were HIV positive, without opportunistic or other viral infections (group A), and 12 were HIV negative (group B).

RESULTS

According to alanine amino-transferase concentrations, four sustained responders and eight non-responders were found in group A; six sustained responders, five relapsers, and one non-responder were found in group B. HCV RNA became negative in one sustained responder of group A and in the six sustained responders of group B. When histological findings of biopsies performed before therapy and 18 months later were compared, no significant changes in the mean value of Knodell's index and subindices were found in group A, whereas in group B Knodell's index, piecemeal necrosis, and focal hepatocellular necrosis decreased significantly.

CONCLUSIONS

In chronic hepatitis C, coinfection with HIV showed a tendency towards a lower response to IFN, although this did not reach statistical significance; however, none of the HIV positive patients developed cirrhosis during the follow up and this should be considered in clinical management of such patients.

Predictors of cytomegalovirus disease, natural history and autopsy findings in a cohort of patients with AIDS

OBJECTIVE

To identify the predictors of acquiring cytomegalovirus (CMV) disease, and to describe natural history, therapeutic management and autopsy findings in affected patients.

DESIGN

Observational study of a consecutive cohort of AIDS patient diagnosed and followed in the same institution.

METHODS

All of the patients with CMV were included. Statistical analyses were performed to establish the risk of acquiring the disease at or after AIDS presentation, survival, and the occurrence and time of relapses in relation to maintenance therapy. The presence of CMV infection at autopsy was also investigated.

RESULTS

CMV disease was diagnosed in 304 (24.8%) out of 1,227 patients, its incidence increasing according to the year of AIDS diagnosis. Women, homosexual men, patients given zidovudine and Pneumocystis carinii pneumonia (PCP) prophylaxis before AIDS, and severely immunodepressed patients were at higher risk for the disease. CMV disease was an independent factor of worse survival (hazard ratio, 1.7 versus PCP; 95% confidence intervals, 1.28-2.13). Patients untreated during the acute phase had a 4.3 higher risk of dying than those treated. Relapses occurred less frequently and later in patients given continuous maintenance treatment (23 out of 113; 17 months) than in untreated patients (13 out of 16; 3 months) or those given discontinuous therapy (22 out of 40; 7 months), whereas survival was independent from treatment. CMV infection was found in 97 out of 134 patients at autopsy, but was unassociated with relapse.

CONCLUSIONS

CMV is a severe disease whose frequency is higher in severely immunodepressed patients. Continuous treatment leads to a lower relapse rate even if it does not change survival or eradicate the infection.

Coinfection of the central nervous system by cytomegalovirus and herpes simplex virus type 1 or 2 in AIDS patients: autopsy study on 82 cases by immunohistochemistry and polymerase chain reaction

We evaluated the frequency and histopathological features of concomitant infections of the central nervous system (CNS) with cytomegalovirus (CMV) and herpes simplex viruses type 1 or 2 (HSV1/2) in a large series of patients who had died from AIDS. Eighty-two autopsy cases with a histological diagnosis of CMV necrotizing encephalitis were examined retrospectively. CMV and HSV1/2 were detected by immunohistochemistry (IHC) with poly- and monoclonal antibodies and by nested polymerase chain reaction (PCR) for HSV 1 and 2 on DNA extracted from paraffin blocks. PCR for a beta-globin genomic sequence was performed in all IHC-positive cases to verify the integrity of extracted DNA. Concomitant CMV/HSV infections were demonstrated by IHC in 13 cases (16%); using monoclonal antibodies, HSV1 was found in 9 cases and HSV2 in 4 cases. In half of the cases, HSV1- or HSV2-positive cells represented more than 25% of immunopositive CMV cells. In all 13 cases, double immunochemical staining showed cells containing both CMV and HSV antigens. PCR for HSV1 and 2 was positive in only 7 of 13 cases (5 HSV1 and 2 HSV2). In the remaining 6 negative cases PCR for beta-globin was also repeatedly negative. HSV1 or 2 infection can be demonstrated by IHC in a significant proportion of AIDS cases with necrotizing CMV encephalitis. Nested PCR for HSV1 and 2 on DNA extracted from formalin-fixed and paraffin-embedded autopsy tissues was positive in only slighty above 50% of IHC-positive cases.

JCV-DNA and BKV-DNA in the CNS tissue and CSF of AIDS patients and normal subjects. Study of 41 cases and review of the literature

SUMMARY

We studied the distribution and localization of the human papova-viruses JCV and BKV in the central nervous system (CNS) and cerebrospinal fluid (CSF) of HIV-positive patients with and without progressive multifocal leukoencephalopathy (PML) as compared with HIV-seronegative patients. The presence of JCV-DNA and BKV-DNA was evaluated by nested polymerase chain reaction (PCR) and in situ hybridization (ISH) on CNS autopsy tissues of AIDS patients with (group A, n = 13) and without (group B, n = 16) PML and of HIV-negative patients (group C, n = 12). PCR for JCV-DNA and BKV-DNA was also performed on CSF samples collected 7-420 days before death in all the 29 AIDS patients. Tissue PCR for JCV-DNA was positive in all the cases in group A, in 44 percent of the patients in group B, and in 33 percent of the patients in group C. ISH was positive in all the cases with PML and in three AIDS cases without PML (12 percent), but negative in all the HIV-negative cases. BKV-DNA was detected in two cases from group A and in one case from group B. CSF was PCR-positive for JCV-DNA in 8 of 13 (62 percent) AIDS patients with PML, but in none of the HIV patients without PML, irrespective of the presence of JCV-DNA in CNS tissues. No CSF sample was positive for BKV-DNA. Our data demonstrates that JCV-DNA and, rarely, BKV-DNA can be detected in the CNS of immunocompromised patients with and without PML and also in the CNS of HIV-negative subjects. However, only HIV-positive patients with clinically evident PML and JCV-DNA in the brain have PCR-detectable JCV-DNA in their CSF.

JCV-DNA and BKV-DNA in the CNS tissue and CSF of AIDS patients and normal subjects. Study of 41 cases and review of the literature

SUMMARY

We studied the distribution and localization of the human papova-viruses JCV and BKV in the central nervous system (CNS) and cerebrospinal fluid (CSF) of HIV-positive patients with and without progressive multifocal leukoencephalopathy (PML) as compared with HIV-seronegative patients. The presence of JCV-DNA and BKV-DNA was evaluated by nested polymerase chain reaction (PCR) and in situ hybridization (ISH) on CNS autopsy tissues of AIDS patients with (group A, n = 13) and without (group B, n = 16) PML and of HIV-negative patients (group C, n = 12). PCR for JCV-DNA and BKV-DNA was also performed on CSF samples collected 7-420 days before death in all the 29 AIDS patients. Tissue PCR for JCV-DNA was positive in all the cases in group A, in 44 percent of the patients in group B, and in 33 percent of the patients in group C. ISH was positive in all the cases with PML and in three AIDS cases without PML (12 percent), but negative in all the HIV-negative cases. BKV-DNA was detected in two cases from group A and in one case from group B. CSF was PCR-positive for JCV-DNA in 8 of 13 (62 percent) AIDS patients with PML, but in none of the HIV patients without PML, irrespective of the presence of JCV-DNA in CNS tissues. No CSF sample was positive for BKV-DNA. Our data demonstrates that JCV-DNA and, rarely, BKV-DNA can be detected in the CNS of immunocompromised patients with and without PML and also in the CNS of HIV-negative subjects. However, only HIV-positive patients with clinically evident PML and JCV-DNA in the brain have PCR-detectable JCV-DNA in their CSF.

Clinical diagnosis of mycobacterial diseases versus autopsy findings in 350 patients with AIDS

Three-hundred fifty consecutively autopsied AIDS patients in Milan, Italy, were studied to determine the frequencies of clinical and postmortem diagnoses of mycobacterial diseases, to evaluate the clinical histories of those patients with mycobacterial diseases, and to investigate the reasons for nondiagnosis of mycobacterial diseases during life. Seventy-eight patients (22.3%) had mycobacterial diseases. In 64 cases (18.3%) the diagnosis was made antemortem and in 50 (14.2%) at autopsy; there were 36 cases of concordant clinical and postmortem diagnoses. Nontuberculous mycobacterioses (NTM) were diagnosed in 41 patients (20 clinical/postmortem diagnoses, 11 clinical diagnoses, and 10 postmortem diagnoses), extrapulmonary tuberculosis (TB) in 19 patients (7 clinical/postmorten, 8 clinical, 4 postmortem), and pulmonary TB in 18 patients (9 clinical/postmorten, 9 clinical). Patients with a clinical diagnosis of mycobacteriosis but with no pathological evidence of disease at autopsy were considered to have recovered on the basis of negative culture findings and prolonged antimycobacterial treatment. In Italian patients with AIDS, NTM occurs less frequently and TB more frequently than in American AIDS patients. At least some of the patients reported in this study seemed to have recovered from mycobacterial disease after prolonged treatment. The lack of diagnosis during life can be attributed to aspecific symptoms, a rapidly terminal course, and the presence of concomitant opportunistic diseases.

Polymorphism-structure relationships of rifamexil, an antibiotic rifamycin derivative

The polymorphism of rifamexil, a rifamycin derivative, has been investigated by thermomicroscopy, differential thermal analysis (differential scanning calorimetry-thermogravimetry), IR spectroscopy, and X-ray powder diffraction. Two crystalline forms, an amorphous material, and three solvates have been studied. The crystal structures of two solvates have also been determined by single-crystal X-ray techniques. Although the overall conformation of rifamexil is very similar in the two compounds, marked differences occur between the two crystal packings, due to differences both in the mutual orientation of the molecules and in the rifamexil-solvent interactions. Multivariate statistical methods have been used to identify the principal structural parameters determining the biological activity of the rifamycins.

Antibiotic GE2270 a: a novel inhibitor of bacterial protein synthesis. II. Structure elucidation

GE2270 A, produced by Planobispora rosea ATCC 53773, inhibits Gram-positive bacteria and anaerobes by acting on the bacterial protein synthesis. The structure has been determined by physico-chemical methods applied to the intact molecule and to the main hydrolysis products. Characterization by UV, IR, NMR (double quantum filter COSY), acid-base ionization, elemental analysis and FAB-MS indicated that GE2270 A is a highly modified peptide having MW 1,289 and formula C56H55N15O10S6, and a weak basic function, and that it belongs to the thiazolyl peptide group of antibiotics. Acid hydrolysis yielded a main product (MW 634), responsible for the chromophoric absorption, and a number of hydrolyzed products of lower MW. 13C NMR inverse techniques and MS studies (EI, positive ion chemical ionization, and collision induced dissociation FAB-MS-MS experiments) on GE2270 A, the chromophoric compound, and the other hydrolysis products led to the complete identification of the various amino acid residues and their sequence. Two out of the six chiral centers have been determined. The structure is thought to originate from modification of a chain of 14 amino acids in a process which creates 6 thiazole rings and one pyridine. The modification process also closes the linear polypeptide to form a cyclic part with an attached side-chain. GE2270 A plausibly has a similar biosynthetic origin to that of other thiazolyl peptide antibiotics such as nosiheptide and micrococcin.

Polymorphism and H-bonding of 2-[1(2H)-oxo-2-phthalazinyl]methylbenzoic acid

The three crystalline and one amorphous forms of the title compound, so far isolated, have been characterized by differential scanning calorimetry, thermomicroscopy, infrared spectroscopy and X-ray powder diffraction. From I was obtained by solidification of the melt at 200 degrees; form II by crystallization from water/ethanol 1/1; form III by grinding of II; the amorphous form by rapid cooling of the melt or by evaporation to dryness of a chloroform solution. From II melts of about 200 degrees and immediately crystallizes into form I, which melts at 210 degrees. Form III transforms into I at 165 degrees. The infrared spectra of form I is different from that of forms II and III, while each form has a different X-ray powder diffraction. From consideration of the infrared functional absorption bands, it can be derived that form I is a dimer with H-bonds between the carboxylic groups, forms II and III are monomers with intramolecular H-bond between the carboxylic group and the hydrazide carbonyl, displaying different crystal packings, and the amorphous form is a mixture of both monomers and dimers, the latters in greater amount.

Polymorphism of rifampicin

The antibiotic rifampicin shows polymorphism. Two crystalline forms, an amorphous form and four solvates (S I and S II from water; S III from tetrahydrofuran; S IV from carbon tetachloride) have been isolated and characterized by thermal analysis, infrared and X-ray powder spectroscopy. The functional I.R. bands have been interpreted as indicative of some structural features involved in the polymorphism: the intramolecular H-bonds between C23--OH and O=C--O--C25, C4--OH and O=C11, and C1--OH and O=C15. The relative physical stabilities of the various forms are reported.