Hepatitis due to human herpesvirus 6B after hematopoietic cell transplantation and a review of the literature.

Human herpesvirus 6B (HHV-6B) is an opportunistic pathogen associated with a growing number of complications in immunocompromised patients. Multiple reports of HHV-6B-associated hepatitis following primary HHV-6 infection and liver transplantation have appeared, but this has only been well documented in 1 patient after hematopoietic cell transplantation (HCT). This report describes a case of acute hepatitis likely caused by HHV-6B in an HCT recipient who was successfully treated with ganciclovir. HHV-6B DNA was demonstrated in plasma and hepatic tissue using quantitative polymerase chain reaction and immunohistochemical stains. Chromosomal integration was ruled out. We review the literature reporting HHV-6B-associated hepatitis, which may be an underappreciated cause of liver disease after HCT.

Microchimerism of maternal origin persists into adult life.

Recent studies indicate that fetal cells persist in maternal blood for decades after pregnancy. Maternal cells are known to engraft and persist in infants with immunodeficiency, but whether maternal cells persist long-term in immunocompetent offspring has not specifically been investigated. We developed sensitive human leukocyte antigen-specific (HLA-specific) PCR assays and targeted nonshared maternal HLA genes to test for persistent maternal microchimerism in subjects with scleroderma and in healthy normal subjects. Nonshared maternal-specific DNA was found in 6 of 9 scleroderma patients. In situ hybridization with double labeling for X and Y chromosome-specific sequences revealed female cells in peripheral blood samples from 2 male scleroderma patients. HLA-specific PCR also frequently revealed persistent maternal microchimerism in healthy control subjects. The mean age of all subjects with maternal microchimerism was 28 years (range: 9-49 years). With few exceptions, mothers of subjects with persistent maternal microchimerism were HLA incompatible with subjects for class I and class II alleles. These results clearly indicate that HLA-disparate maternal cells can persist in immunocompetent offspring well into adult life. The biological significance of maternal microchimerism and whether it might contribute to autoimmune disease requires further investigation.

Ultrastructural localization of stem cell factor in canine marrow-derived stromal cells.

Stromal cell lines derived from canine long-term bone marrow cultures (LTBMC) were characterized regarding the expression of growth factors and especially the localization of stem cell factor (SCF) (c-kit ligand). One cell line (DO64) was immortalized by transformation with a retroviral vector containing the open reading frames (ORFs) E6 and E7 of the human papilloma virus type 16 (HPV-16). Transfection did not change cellular characteristics but rendered the cell line more independent from culture conditions. The transformed line DO64 consisted mainly of fibroblast-like cells. In addition, some cells showed endothelial and some smooth-muscle cell features. Stromal cells expressed a broad spectrum of surface markers, including low levels of major histocompatibility-complex (MHC) class-II antigens. A new murine monoclonal antibody (MAb), RG7.6 (IgG1), specific for canine SCF, recognized the majority of fibroblast-like stromal cells. The staining pattern for SCF showed perinuclear and intracytoplasmic dense areas. Immunoelectron microscopy revealed the localization of SCF in secretory vesicles, the perivesicular cytoplasm, and bound to the cytoplasmatic membrane. RNA analysis showed that stromal cells transcribed, in addition to SCF, messages for granulocyte colony-stimulating factor (G-CSF), granulocyte-monocyte CSF (GM-CSF), interleukin-6 (IL-6), and transforming growth factor-beta (TGF-beta). In summary, we have established and characterized canine marrow-derived stromal cell lines, and using the new MAb RG7.6, we have localized SCF to cytoplasmatic vesicles as well as the membrane of stromal cells.

HSV, CMV, and HPV in human neoplasia.

We are studying the role of sexually transmitted viruses in the development of human tumors. The persistence of herpes simplex virus, cytomegalovirus, and human papillomavirus nucleic acid sequences has been examined using cloned viral DNA sequences as probes. The relationship of the viruses to various stages in the progression of neoplasia is examined, with particular reference to the role of viral and/or cellular genes in the initiation, promotion, and maintenance of the neoplastic phenotype. The human tumors of major interest in this context are carcinomas of the cervix, vulva, and anus and Kaposi's sarcoma. The minimal fragment of HSV-2 DNA detected in cervical tumors is contained within a 656-bp sequence that can be used in transfection experiments to transform rodent cells in vitro to a malignant phenotype. However, neither this fragment nor any other is consistently retained in cervical tumors, suggesting that this viral DNA may initiate but not maintain the transformed phenotype.

The effect of prophylactic fluconazole on the clinical spectrum of fungal diseases in bone marrow transplant recipients with special attention to hepatic candidiasis. An autopsy study of 355 patients.

We reviewed 355 autopsies performed between 1990 and 1994 at a major marrow transplant center to determine whether fluconazole prophylaxis prevented visceral fungal infection. Fluconazole prophylaxis was defined by a minimum of 5 prophylactic doses. Fungal infection (any site) was found in 40% of patients transplanted and autopsied at the center. Overall, the proportion of autopsies with any fungal infection was not different for those patients receiving no fluconazole prophylaxis versus those with prophylactic fluconazole. With fluconazole prophylaxis, candidal infections were less frequent, decreasing from 27% to 8%, while Aspergillus infections were more frequent, increasing from 18% to 29%. No increase in deaths related to non-albicans Candida infections was seen. Of the 329 patients with livers examined, hepatic infection caused by Candida species was significantly less common in patients who had received fluconazole. Fungal liver infection was found in 31 patients (9%), 16% of those who were not treated with fluconazole and 3% of those who were treated with fluconazole. Since patients with candidal infections died earlier after marrow transplant than patients with mold infections, we speculate that a longer length of survival may dispose toward acquisition of mold infections. Fluconazole prophylaxis in this cohort of marrow transplant patients undergoing autopsy resulted in a significant reduction in infection caused by Candida species and an increase in mold infections.

Viral diagnosis by in situ hybridization. Description of a rapid simplified colorimetric method.

An improved method of colorimetric in situ hybridization for the diagnosis of viral infections in standard formalin-fixed, paraffin-embedded tissue sections has been developed. This method employs a 2-hour hybridization with biotin-labeled DNA probes followed by direct colorimetric detection with avidin-alkaline phosphatase complexes. Visual results are obtained within 8 h of cutting the tissue section. Specific histologic localization of cytomegalovirus and adenovirus genetic information has been achieved in infected lung tissues from autopsy or biopsy. Simultaneous denaturation of tissue and probe DNA at elevated temperature (100-105 degrees C) resulted in increased signal. It is our suggestion that these denaturing conditions may be required to denature more fully formalin cross-linked tissue DNA and favor penetrance of probe into the tissues. Comparison of the results of hybridization and viral culture for the diagnosis of CMV infections suggest that in clinical situations hybridization will allow specific diagnosis of productive viral infection more rapidly than viral culture with some loss in sensitivity. Colorimetric in situ DNA hybridization offers the surgical pathologist a powerful new technique that provides an alternative to immunocytochemistry and electron microscopy in the diagnosis of viral pathogens.

Plasma polymerase chain reaction for cytomegalovirus DNA after allogeneic marrow transplantation: comparison with polymerase chain reaction using peripheral blood leukocytes, pp65 antigenemia, and viral culture.

In a prospective longitudinal study, detection of cytomegalovirus (CMV) DNA in plasma (plasma polymerase chain reaction [PCR]) was compared with PCR of CMV DNA in peripheral blood leukocytes (PBL PCR), the CMV pp65 antigenemia assay, and viral cultures from blood, urine, and throat of 29 patients, 14 of whom received pp65 antigenemia-guided early ganciclovir treatment and 15 of whom received ganciclovir at engraftment. Among 328 blood samples tested by all methods, PBL PCR was the most sensitive test, followed by the pp65 antigenemia assay, plasma PCR, and viremia. In the 14 patients who received pp65 antigenemia-guided early treatment, the incidence of PBL PCR, pp65 antigenemia, plasma PCR, and viremia before day 100 was 79%, 79%, 71%, and 27%, respectively, with a median day of onset of day 32, 42, 45, and 51, respectively. Nine patients (64%) became positive by PBL PCR, pp65 antigenemia, and plasma PCR. Of 15 patients who were treated with ganciclovir at engraftment, 12 (80%) became positive by PBL PCR, plasma PCR, and/or pp65 antigenemia while receiving ganciclovir; 3 (20%) had breakthrough infection with all three methods, including 2 with high-grade antigenemia (more than three positive cells in duplicate staining); none of these patients subsequently developed positive CMV cultures or disease. In 49 specimens, PBL PCR and/or pp65 antigenemia assay could not be performed because of insufficient neutrophil counts. In conclusion, the sensitivity of plasma PCR is significantly lower than that of PBL PCR but similar to that of the pp65 antigenemia assay. Plasma PCR may be particularly useful in clinical situations in which a less sensitive and possibly more specific assay is warranted or in which leukocyte counts are inadequate to perform cell-based assays.

Idiopathic pneumonia syndrome: changing spectrum of lung injury after marrow transplantation.

BACKGROUND: The aim of our study was to describe the incidence, clinical course, and risk factors for the idiopathic pneumonia syndrome (IPS), compared with those previously described for "idiopathic pneumonia," after bone marrow transplantation (BMT). METHODS: Our study design was a case-series review with determination of risk by comparison with unaffected controls by log-rank or Fisher's exact (two-tailed) test and logistic regression analyses. The study group comprised 1165 consecutive marrow recipients at a single center from 1988 to 1991. RESULTS: IPS was documented in 85 BMT recipients (7.3%) by bronchoalveolar lavage (n=68), open lung biopsy (n=3), or autopsy (n=14). The calculated actuarial incidence for IPS within 120 days after BMT was 7.7%. Median time to onset was 21 days (mean 34+/-30). Hospital mortality was 74%, and 53 BMT recipients (62%) died with progressive respiratory failure. IPS resolved in 22 patients (26%); 18 patients (21%) survived to discharge. Mechanical ventilation was required by 59 BMT recipients (69%), within a median of 2 days of onset of infiltrates. Two of these 59 recipients (3%) survived to discharge. Pulmonary infection (predominantly fungal) was noted in 7 of 25 (28%) BMT recipients who had an autopsy. Potential risk factors for IPS were assessed in univariate and multivariate logistic regression analyses. Although the incidence was not significantly different between autologous (5.7%) and allogeneic marrow recipients (7.6%), risks were identified only for the latter: malignancy other than leukemia (odds ratio=6.5 compared with aplastic anemia), and grade 4 graft-versus-host disease (odds ratio=5.4 compared with lower grades). No factors were associated with recovery. CONCLUSIONS: The incidence of idiopathic lung injury seems lower, the onset earlier, and the risk factors different from those previously reported. The major risks seem to be regimen-related toxicity and multi-organ dysfunction associated with alloreactive processes.

Prevention of transmission of hepatitis C virus in bone marrow transplantation by treating the donor with alpha-interferon.

Transmission of hepatitis C virus (HCV) in the setting of allogeneic bone marrow transplantation can occur through an infected marrow donor. Prevention of transmission may reduce the risks of peritransplant complications. We describe a 43-year-old patient with chronic myelogenous leukemia whose HLA-identical donor was found to be HCV antibody positive and HCV RNA positive by polymerase chain reaction (PCR). The patient was HCV antibody negative and HCV RNA negative by PCR of the serum. For 6 months before bone marrow transplantation, the donor was treated with alpha-interferon at a standard dose. After 3 months, HCV RNA was no longer detectable by PCR. Interferon was discontinued 1 week before harvest. Bone marrow cellularity was normal. Engraftment was prompt. The recipient's serum remained negative for HCV RNA at 1, 3, 5, and 10 months after transplantation. Hepatitis C transmission from a viremic donor to an HCV-seronegative recipient may be preventable by treating the donor with alpha-interferon.

Recognition and rapid diagnosis of upper gastrointestinal cytomegalovirus infection in marrow transplant recipients. A comparison of seven virologic methods.

This is a retrospective study of 54 consecutive upper gastrointestinal endoscopies in marrow graft recipients performed to determine the incidence and distribution of CMV infection in symptomatic patients and to compare the sensitivities of 7 CMV detection techniques. At each endoscopy, 3 biopsies were obtained from the esophagus, stomach, and duodenum. Each of the 3 biopsies was assayed for CMV by different techniques. Enteric CMV was identified by one or more techniques in 52 of 486 (11%) biopsies from 14 infected patients. All patients infected with CMV initially had nausea and vomiting. In 13 of these patients, there was esophageal CMV, often associated with stomach (10 patients) and duodenal (7 patients) involvement. CMV infection of the esophagus was never identified cytologically in esophageal imprints or histologically, immunohistologically, or by DNA hybridization in esophageal epithelial cells. The most sensitive diagnostic methods were conventional and centrifugation cultures, which each identified CMV in 17 of the 30 (57%) organs positive by any technique. Indirect fluorescent antibody (IFA) staining for a late CMV antigen detected 53%, followed by in situ DNA hybridization (40%), IFA and immunoperoxidase (IP) staining for an early CMV antigen (37% and 43%), and routine histology (30%). Although no single detection technique is completely adequate for the rapid identification of CMV in small endoscopic biopsies, centrifugation culture is the method of choice, with supplementary immunohistology and in situ hybridization of archival tissue if needed.

Producing single-stranded DNA probes with the Taq DNA polymerase: a high yield protocol.

We report an efficient procedure to synthesize either single- or double-stranded probes labeled with biotin-11-dUTP, biotin-21-dUTP or digoxigenin-11-dUTP. To produce the single-stranded probe, only a single primer is utilized in a Taq polymerase amplification of 55 cycles. A cytomegalovirus probe is presented. This procedure allows easy production of nonradioactively labeled pure single-stranded probes of any desired length and specificity.

A single-step silver enhancement method permitting rapid diagnosis of cytomegalovirus infection in formalin-fixed, paraffin-embedded tissue sections by in situ hybridization and immunoperoxidase detection.

A single-step silver enhancement method was developed which intensifies the polymerized nickel-complexed diaminobenzidine (Ni-DAB) reaction product of peroxidase. With such enhancement, an in situ hybridization procedure can be performed in less than 8 hr by using a 2-hr hybridization incubation and direct detection. Cytomegalovirus (CMV)-infected lung sections were hybridized in situ for 2 hr with a biotinylated CMV genomic-length probe. The probe was detected directly with avidin-biotinylated peroxidase using Ni-DAB as the substrate, and the reaction product was enhanced with silver. Silver was deposited only on the Ni-DAB and not on normally argyrophilic substances. Indirect detection of the probe using a sandwich technique before silver enhancement proved more sensitive, but the length of the procedure was increased without substantially changing the result (infection vs. no infection). Sensitivity was also improved by omitting the dehydration step before applying the probe, and by increasing the temperature and duration of denaturation. In a blinded study of 21 open-lung biopsies, 13 of 13 culture-negative specimens were negative by hybridization, and 7 of 8 culture-positive specimens were positive by hybridization. Modified short hybridization with a biotinylated probe and silver-enhanced direct detection therefore provides a rapid but sensitive method for diagnosis of viral infection.

Detection of viral DNA and RNA by in situ hybridization.

Using cloned restriction endonuclease fragments of Herpes simplex virus (HSV), human papillomavirus (HPV), and cytomegalovirus (CMV) DNA as probes, viral DNA and RNA sequences have been detected in human tissues. The probes were labeled either with a radioactive isotope, for subsequent detection by autoradiography, or with biotin. This latter technique has been successfully used to visualize HPV DNA in tissues that have been fixed in formalin and embedded in paraffin, and is therefore of value in retrospective studies of histological specimens. HPV DNA was detected under non-stringent conditions (Tm = -42 degrees C) with heterologous probes in plantar and common warts, laryngeal papillomas, and anogenital condylomas. The specific type of HPV was established using stringent hybridization conditions (Tm = - 17 degrees C). Results from these and from malignant tissues show the distribution and localization of HSV and HPV RNA and DNA sequences in malignancies of squamous cell origin in the anogenital region. Both HSV and HPV DNA sequences have occasionally been detected in the same tumor, providing a further impetus to test the hypothesis that an initiator-promoter relationship might involve these common human viruses in the development of some tumors.

Anatomic patterns of Ga-67 distribution in localized and diffuse peritoneal inflammation: case report.

Radiogallium imaging may be useful in identifying localized and diffuse peritoneal disease. The posterior peritoneal reflections can be delineated, providing further anatomical differentiation of disease processes in the peritoneum. This may allow separation of peritoneal from retroperitoneal disorders.

Gallium imaging in pulmonary artery sarcoma mimicking pulmonary embolism: case report.

Primary pulmonary artery sarcoma provides perfusion-ventilation images, as well as arteriographic studies, that can suggest pulmonary embolism. The awareness of atypical correlation among the studies for pulmonary embolism can lead to an early suspicion of pulmonary artery tumor. Imaging with 67Ga-citrate may facilitate earlier diagnosis.

Gallium-67 spread to the anterior pararenal space in pancreatitis: case report.

Gallium imaging has been of value in revealing the spread of inflammatory pancreatic disease to the anterior pararenal space. Recognition of this retroperitonel space and the potential usefulness of its imaging in the diagnosis of pancreatic diseases are discussed.

Anatomic correlations in radiogallium imaging of the peritoneum and retroperitoneum.

Radiogallium (67Ga) imaging of the abdomen and pelvis has been useful not only in detecting inflammations in these regions, but in pointing out their precise anatomic localization. Once the anatomic site is determined, it is often possible to infer the source of origin of the problem (such as ruptured viscus or pancreatitis). Interpretation of the images depends on recognition of patterns that define known anatomic boundaries such as the transverse mesocolon, root of the small mesentery, perirenal space, and pararenal space, or else show diffuse peritoneal uptake. The anatomic patterns may have continued usefulness in future studies, such as when radiolabeled leukocytes are employed to localize inflammations.

Diffuse intestinal ulceration after marrow transplantation: a clinicopathologic study of 13 patients.

The cases of 13 allogeneic marrow transplant recipients who had undergone laparotomy for manifestations of severe enteritis were reviewed to determine the causes of the severe intestinal disease and to assess the relation between clinical, histologic, and microbiologic findings. Laparotomies were performed a median of 63 days (range, 11 to 273 days) after transplantation for suspected peritonitis, intestinal obstruction, or bleeding. Intestinal tissue was available from small bowel resections in nine patients, intraoperative biopsies in one, and from autopsies in three patients who died shortly after laparotomy. Widespread small bowel ulceration was present in all 13 cases. Four causes of ulceration were identified: chemoradiation toxicity (n = 2), acute graft-versus-host disease (GVHD) (n = 5), opportunistic infections superimposed on either GVHD or toxicity from chemotherapy (n = 4), and Epstein-Barr virus-associated lymphoproliferative disorder (n = 2). Intestinal infections, unrecognized before laparotomy, were due to cytomegalovirus (CMV), herpes simplex virus (HSV), adenovirus, and Torulopsis glabrata. CMV- and HSV-infected cells, often lacking diagnostic inclusions, were identified in the intestine by in situ hybridization with biotinylated DNA probes. Eleven patients died in the perioperative period, and two died 452 and 558 days after surgery of complications of chronic GVHD. Poor outcomes were related to extensive intestinal involvement, which was commonly underestimated before surgery, failure to diagnose intestinal infections early, poor marrow function, impaired immunity, and refractoriness of severe GVHD.

Widespread presence of histologically occult cytomegalovirus.

Disseminated cytomegalovirus (CMV) has been investigated by in situ hybridization in formalin-fixed paraffin-embedded tissue sections with biotinylated DNA probes. Two cases of disseminated CMV infection were studied at autopsy by this highly specific technique. The presence of CMV in cytomegalic cells is readily shown. In addition, CMV has been detected and localized in many normal-appearing cells. This occult infection occurs in cardiac myocytes, hepatocytes, spleen and lymph node reticular cells, endometrial stromal and glandular cells, and breast stromal cells, as well as in cells in the renal glomerulus, tubule, and interstitium, adrenal cortex and medulla, fallopian tube submucosa, myometrium, and anterior pituitary. Cytomegalovirus infection of endothelial cells has been further documented by immunohistochemical methods utilizing antibody to Factor VIII. These findings suggest that CMV disseminates hematogenously throughout the body, initiating necrotizing foci of infection. The appearance of many diffuse foci suggests that local viral spread occurs via endothelial cell infection. Surprisingly , lymphocyte involvement was not observed.

Early detection and treatment of cytomegalovirus infections in marrow transplant patients: methodological aspects and implications for therapeutic interventions.

Major advances have been made in the early detection of CMV infection after marrow transplant by the introduction of the polymerase chain reaction (PCR) and the CMV antigenemia assay. Numerous studies have established clinical correlations of these techniques but there is a need for technical standardization as assay sensitivity may vary considerably with different modifications. Current prevention strategies for CMV disease after marrow transplantation, including options on how the antigenemia assay and PCR assays may be used in early treatment strategies, are discussed.