Molecular epidemiology of HTLV type I in Japan: evidence for two distinct ancestral lineages with a particular geographical distribution

Japan is one of the highest endemic areas of the world for human T cell leukemia-lymphoma virus type I (HTLV-I). To gain new insight as to the origin of this virus in Japan and especially in the southern islands of the archipelago, we investigated the long terminal repeat (LTR) of 67 newly isolated HTLV-I proviral DNAs from peripheral blood mononuclear cells of HTLV-I-infected individuals for their restriction fragment length polymorphism (RFLP). The specimens were from Japanese living in different geographical areas (Hokkaido, Honshu, Kyushu, or the Ryukyu Islands) of Japan (59 cases) or Americans of Japanese ancestry living in Hawaii (8 cases). The analysis of the results, together with data for the 19 previously published LTR sequences, demonstrated the existence of 2 subtypes of HTLV-I in Japan. The first, which we propose to name Japanese subtype (previously named subtype III), is more frequent (67 of 86: 78%) than the second, the cosmopolitan subtype (previously named subtype II) (19 of 86: 22%). In parallel, a fragment of 413 base pairs of the U3/R region (nucleotide 22 to 434) was cloned and sequenced from 10 of the new Japanese samples. The alignment of these sequences and their comparison and phylogenetic analysis with previously published LTR HTLV-I sequences, demonstrated clearly the existence of the two distinct molecular subtypes of HTLV-I in Japan, diverging in this LTR region by about 1.6%. Furthermore, the study of the geographical distribution of the 2 subtypes among the 80 samples from patients whose place of residence in Japan was known showed an uneven distribution. While the Japanese subtype was present in all parts of Japan, the cosmopolitan subtype seemed to cluster in the southern islands of the archipelago (i.e., Kyushu and the Ryukyu Islands) as well as in immigrants from those areas who had lived in Hawaii for decades. These new molecular data raise questions and suggest hypotheses, discussed here, concerning the origin and means of dissemination of these human retrovirus subtypes in Japan.

Is simple fistula-in-ano simple?

PURPOSE

A study of 523 fistulas of cryptoglandular origin operated on between January 1985 and December 1991 at the Lehigh Valley Hospital was undertaken for the purpose of establishing whether the "so-called" simple fistula-in-ano has a favorable outcome. High transsphincteric fistulas with or without high blind tract, suprasphincteric, extrasphincteric, and horseshoe fistulas as well as fistulas associated with inflammatory bowel disease were excluded.

METHODS

Four-hundred sixty-one patients with anal fistulas classified as simple fistulas-in-ano (uncomplicated transsphincteric, low and high blind track intersphincteric) were studied retrospectively. There were 310 males and 151 females with an average age of 42 years and mean follow-up of 34 months.

RESULTS

Thirty (6.5 percent) patients developed recurrent fistulas: 16 (53.3 percent) because of missed internal openings at initial surgery, six (20 percent) attributed to missed secondary tracks, five (16.7 percent) because of premature fistulotomy wound closure, and three (10 percent) because of miscellaneous factors.

CONCLUSION

All so-called simple fistulas-in-ano may not have readily detectable primary openings and may possess secondary tracks which preclude their behavior as simple fistulas.

Hemorrhage following colonoscopic polypectomy

Clinically significant hemorrhage following colonoscopic polypectomy may occur primarily as the polyp is removed or manifest itself days to weeks later secondary to clot dissolution. The rate of hemorrhage following colonoscopic polypectomy ranges widely from 0.3 to 6.1 percent, depending on whether the data are derived from studies using the number of patients or number of polypectomies. A retrospective study was performed in our institution to study 4,721 patients who underwent polypectomy between January 1987 and December 1991. Twenty (0.4 percent) of these patients required hospital admission because of 9 primary and 11 delayed hemorrhages. Fifty-four polyps were removed from these patients: 11 in the right colon, 7 in the transverse colon, 17 in the descending colon, and 19 in the sigmoid colon. Eight polyps were 2 cm or larger, 10 were pedunculated, and 44 were sessile. Six patients underwent cauterization or resnaring of the bleeding polyp site, one patient underwent subtotal colectomy, and the remainder of the patients stopped bleeding spontaneously. Factors that could be associated with the outcome of hemorrhage include patient age, size, location, number and morphology of polyps (i.e., sessile or thick stalk), and use of anticoagulants. An experienced endoscopist with knowledge of electrosurgical and technical principles may be the most important factor for prevention of postpolypectomy bleeding.

Genetic determinants of dengue type 4 virus neurovirulence for mice

Mouse-adapted dengue type 4 virus (DEN4) strain H241 is highly neurovirulent for mice, whereas its non-mouse-adapted parent is rarely neurovirulent. The genetic basis for the neurovirulence of the mouse-adapted mutant was studied by comparing intratypic chimeric viruses that contained the three structural protein genes from the parental virus or the neurovirulent mutant in the background sequence of nonneurovirulent DEN4 strain 814669. The chimera that contained the three structural protein genes from mouse neurovirulent DEN4 strain H241 proved to be highly neurovirulent in mice, whereas the chimera that contained the corresponding genes from its non-mouse-adapted parent was not neurovirulent. This finding indicates that most of the genetic loci for the neurovirulence of the DEN4 mutant lie within the structural protein genes. A comparison of the amino acid sequences of the parent and its mouse neurovirulent mutant proteins revealed that there were only five amino acid differences in the structural protein region, and three of these were located in the envelope (E) glycoprotein. Analysis of chimeras which contained one or two of the variant amino acids of the mutant E sequence substituting for the corresponding sequence of the parental virus identified two of these amino acid changes as important determinants of mouse neurovirulence. First, the single substitution of Ile for Thr-155 which ablated one of the two conserved glycosylation sites in parental E yielded a virus that was almost as neurovirulent as the mouse-adapted mutant. Thus, the loss of an E glycosylation site appears to play a role in DEN4 neurovirulence. Second, the substitution of Leu for Phe-401 also yielded a neurovirulent virus, but it was less neurovirulent than the glycosylation mutant. These findings indicate that at least two of the genetic loci responsible for DEN4 mouse neurovirulence map within the structural protein genes.

Outcome of delayed hemorrhage following surgical hemorrhoidectomy

Delayed hemorrhage following surgical hemorrhoidectomy is a well-recognized complication. Emergency treatment may include suture ligation, anal packing, or other means of tamponade. At the Lehigh Valley Hospital, 27 patients were seen with the complication of delayed hemorrhage over an eight-year period from 1983 to 1990, for an incidence of 0.8 percent. Twenty-five patients (93 percent) underwent surgery primarily for hemorrhoidal disease; one patient had hemorrhoids removed in addition to a sphincterotomy for anal tissue, and the remaining patient had hemorrhoidectomy with fistulotomy. The mean interval from the operation to hemorrhage was six days. Treatment modalities included bedside anal packing in 20 patients (74 percent), observation alone in five patients (18 percent), and suture ligation in the operating room in two patients. Anal packing was successful in controlling postoperative hemorrhage in 20/20 patients, but late complications requiring reoperation developed in 15 percent.

Unusual morphology of a virus which produces carbon dioxide sensitivity in mosquitoes

A virus, named Matsu, presumed to be the etiologic agent of hereditary sensitivity to carbon dioxide in Culex quinquefasciatus mosquitoes, was adapted to growth in the C6/36 line of Aedes albopictus cells. Though it was expected that the mosquito virus would be a rhabdovirus like sigma, the etiologic agent of hereditary carbon dioxide sensitivity in Drosophila melanogaster flies, that was not the case. The virion of Matsu was found to be unlike any previously described virus. It was pleomorphic, enveloped, from 200 to 550 nm in maximum diameter, and contained from three to several dozen virus-like polyhedral structures approximately 30 nm in diameter.

Concordance of familial characteristics in Crohn's disease and ulcerative colitis

The diagnosis of inflammatory bowel disease (IBD) in a proband increases the probability of a parallel IBD diagnosis in a family member. In this study, we were able to confirm the IBD diagnosis in 35 (9.9 percent) of the relatives of 352 registry probands. To confirm a proband's report of a positive family history of IBD, efforts were made to directly contact all first-degree relatives regardless of their IBD status (parents, siblings, and children). Consent to contact family members was obtained from the proband, who furnished the registry personnel with names, addresses, and phone numbers. We then attempted to contact each identified relative by phone. After verbal consent was obtained, family members were asked if they had been diagnosed with IBD. This diagnosis was confirmed by contacting the relative's physician. A McNemar (chi 2 Mc) matched-pair analysis was used to analyze concordance between the proband and the affected family member. Within the CD/CD (Crohn's disease) concordant pairs, sex was a significant risk factor. Sex was not a significant risk factor within the UC/UC (ulcerative colitis) concordant pairs. In the concordant surgery pairs, no surgical procedure was a significant risk factor for the prediction of a similar surgical procedure for the affected relative. In concordant extraintestinal complications, only the appearance of a skin rash was significantly related to the appearance of a skin rash in the affected relative.

Practice parameters for the management of anal fissure. The Standards Task Force American Society of Colon and Rectal Surgeons

It should be recognized that these guidelines should not be deemed inclusive of all proper methods of care or exclusive of methods of care reasonably directed to obtaining the same results. The ultimate judgment regarding the propriety of any specific procedure must be made by the physician in light of all of the circumstances presented by the individual patient.

Is anorectal surgery on chronic dialysis patients risky?

Patients on chronic hemodialysis for end-stage renal disease (ESRD) may develop anorectal problems necessitating surgery. From January 1984 to December 1987, 18 ESRD patients underwent anorectal surgery. During this period, a mean of 215 patients underwent dialysis. Patients with ESRD present with characteristic problems: chronic constipation, need for dialysis pre- and postoperatively with heparin infusion, anemia, anticoagulation secondary to the consequences of uremia, and significant medical problems including coronary artery disease, diabetes mellitus, hypertension, and chronic obstructive pulmonary disease (COPD). Two patients had concomitant anal fissure, two had fistula-in-ano, and one had an acute perianal abscess. In two patients, the postoperative course was complicated by hemorrhage and, in one patient, by abscess formation. There was no delay in wound healing compared with a cohort group. The essentials of perioperative management are discussed with respect to timing of dialysis, methods of anesthesia and pain management, coagulation screening, and complications. Patients on well-managed chronic dialysis will tolerate anorectal surgery without undue jeopardy.

Assessment of disease activity in a registry of Crohn's disease patients in eastern Pennsylvania

The objectives of this report are to: 1) compare the Crohn's disease (CD) patient's assessment of their well-being to the physician's assessment of the patient's well-being, 2) use the existing Crohn's disease indices (CDI) in comparing the severity of CD with the patient's self assessment, and 3) compare the CDI with the physician's assessment of patient well-being. The CDI included in this study were the National Cooperative Crohn's Disease Study Index (CDAI), Harvey & Bradshaw Index (HBI), Oxford Index (OXI), Modified-Organisation Mondiale de Gastroenterologie (OMGE), Cape Town Index (CTI), Bristol Index (BRI), St. Marks Index (SMI) and the Van Hees index (VHI). The patient and physician correlation of well-being was poor but statistically significant. The patient assessment of well-being was best measured by the CTI (r = 0.635, p less than or equal to 0.001), followed closely by the OMGE and CDAI (r = 0.615, p less than or equal to 0.001 and r = 0.582, p less than or equal to 0.001 respectively). The physician assessment of well-being was best measured by the VHI (r = 0.527, p less than or equal to 0.001).

Clostridium difficile--a common and costly colitis

Clostridium difficile infection manifests as a self-limiting diarrhea, protracted colitis, or toxic pseudomembranous colitis. The incidence of C. difficile in a 514-bed community hospital was studied retrospectively; 155 patients of a total 18,262 admitted during 1988 were identified with C. difficile as an admitting or subsequent diagnosis. The method of diagnosis, mode of therapy, and related costs were analyzed. We have determined that education, with an emphasis on pathogenesis and prevention, is necessary to reduce the incidence in the hospital and the cost to the patient.

Hemorrhoidectomy during pregnancy: risk or relief?

Acute hemorrhoidal crisis can occur in the pregnant female. When medical therapy fails to relieve pain, operative intervention may be necessary. The surgeon, however, may be reluctant to operate due to potential complications to the mother and fetus. From July 1983 to July 1989, hemorrhoidectomy was performed in 25 of 12,455 pregnant women (0.2 percent) who delivered in our institution. Twenty-two women were in their third trimester, 80 percent were multiparous, and each had a remote history of hemorrhoidal symptoms, including intermittent pain, bleeding, and protrusion. Closed hemorrhoidectomy was performed under local anesthesia. The surgery was directed at removing only symptomatic disease, which included three quadrants in 14 patients, two quadrants in seven patients, and one quadrant in four patients. All patients experienced relief of intractable pain the day after surgery, except one patient who required a hemostatic packing during the immediate post-operative period. There were no other maternal or fetal complications. Subsequent follow-up for anorectal disease ranged from 6 months to 6 years. Six (24 percent) patients required additional hemorrhoid treatment. Hemorrhoidectomy in selected pregnant patients is safe in our experience.

Horseshoe abscess fistula. Seton treatment

A study was undertaken to analyze seton fistulotomy with counter drainage as a treatment modality for horseshoe abscess fistula. In a previous report of 27 patients with partial or complete horseshoe abscess fistula, 24 patients underwent primary fistulotomy and counter drainage with a recurrence rate of 28.6 percent. Two patients were treated by seton fistulotomy and counter drainage with no recurrence. Therefore, nine additional patients underwent this procedure. Recurrent horseshoe abscess fistula occurred in 2 of 11 patients (18.1 percent). Seton fistulotomy with counter drainage has become the authors' operative procedure of choice for horseshoe abscess fistula. This method may prove more effective if the true primary abscess cavity is identified, the seton is removed appropriately, and postoperative care of the cavity is adequate. Method of management is discussed.

Physical examination of the anorectum: a systematic technique

Advances in medical technology have enabled the colorectal specialist to use sophisticated methodology and precision instrumentation for diagnosing disease. However, one must not overlook the value of the thorough, systematically approached anorectal examination for initially identifying abnormalities.

Mycosis fungoides bullosa

A case of mycosis fungoides bullosa is presented. The results in our study confirmed that the predominant atypical lymphoid cells in the bullae, peripheral blood, and involved lymph nodes expressed the T-cell helper phenotype using immunophenotyping techniques. The literature is reviewed, confirming that our case demonstrated cells of the T-helper phenotype, not only in the skin but also in the blood and lymph node tissue. Bullous lesions in mycosis fungoides are rare.

Mosquito collection in endemic areas of Japanese encephalitis in Hokkaido, Japan

A study was conducted during 1985 and 1986 to evaluate the roles of mosquito species as possible vectors of Japanese encephalitis (JE) virus in Hokkaido. The number of Culex tritaeniorhynchus was very low among the four pig farms where outbreaks of abortion caused by JE virus were observed in swine populations. At one farm near Sapporo, only one Cx. tritaeniorhynchus was found among a total of 510 mosquitoes collected during the survey period from July to October 1985, even when JE virus activity among sentinel pigs was revealed by seroconversion. At another farm in the south, no individuals of this mosquito species were found among 987 mosquitoes collected at the time of the outbreaks of abortion. Cx. pipiens pallens, Anopheles species, Aedes vexans nipponii, and Ae. japonicus were predominant over Cx. tritaeniorhynchus. Cx. tritaeniorhynchus, almost a solve vector species of JE virus in the southern part of Japan, is probably not a vector of the virus in Hokkaido. The collected mosquitoes (2,332 from 1985 and 1,403 from 1986) were processed for virus isolation but no JE virus was isolated. More extensive field studies are necessary to provide further information on the role of mosquito species other than Cx. tritaeniorhynchus in the transmission of JE virus in the northern limits of its range including Hokkaido.

Mass screening for colorectal cancer

A voluntary community colorectal cancer screening project to detect occult blood in the stool of asymptomatic individuals was undertaken; 49,353 Hemoccult II kits were distributed. A total of 23,674 completed kits were returned to a central repository and processed (compliance rate, 48 percent); 851 participants had positive results (3.6 percent). Of the 640 who underwent further medical evaluation, 299 participants (46.7 percent) who had adequate follow-up had no evidence of disease. Diverse disease entities were detected in 341 participants, which was 1.4 percent of those enrolled. Forty-one patients (0.17 percent) showed significant findings that included 29 cancers (0.12 percent) and 12 (0.05 percent) noninvasive malignant polyps. Of the cancers, there were 27 colorectal, one non-Hodgkin's lymphoma, and one carcinoma of the vocal cord. In addition, 107 patients (0.45 percent) had benign polyps and 193 patients (0.82 percent) had various diseases of the gastrointestinal tract and other medical conditions. The cost of the program was modest and the results conformed to those found in previous screening surveys. The heightened public awareness of testing for colorectal disease and the detection of early lesions justifies the guaiac test screening program for mass survey.

Recovery of virus from the liver of children with fatal dengue: reflections on the pathogenesis of the disease and its possible analogy with that of yellow fever

Dengue viruses types 2 or 3 were recovered from the liver of 5 out of 17 children who were suspected to have died of dengue. Among the 5 children with liver isolates, virus was also recovered from the heart blood, spleen and midbrain of one and from the spleen of another. Attention is drawn to the many similarities in the clinical manifestations of yellow fever and severe dengue, their indistinguishable liver lesions and the close relationship of the viruses themselves. In view of the liver isolates reported here and those described by others, it is suggested that the pathogenesis of the two diseases may be analogous.

A longitudinal study of the prevalence of Japanese encephalitis virus in adult and larval Culex tritaeniorhynchus mosquitoes in northern Taiwan

Adult females and larvae of Culex tritaeniorhynchus were collected year-round for 3 1/2 years at a site near Taipei, Taiwan. One hundred sixty-four isolates of Japanese encephalitis (JE) virus were obtained from approximately 142,000 adult females and 1 isolate of the virus was obtained from approximately 382,000 larvae. Virus was recovered from adult females every year, except the first, beginning in May. The single larval isolate was from specimens collected in June. The vertical transmission of JE virus in Cx. tritaeniorhynchus as a possible inter-epidemic viral survival mechanism is examined.

Disease exacerbation caused by sequential dengue infections: myth or reality?

Dengue can be caused by any one of four viruses that are antigenically related but not cross-protective. It has been proposed that the disease may be more severe if an infection with one dengue serotype follows infection with another serotype. Both experimental and epidemiologic data have been cited to substantiate this concept, but the present reviewer does not find the data convincing. The issue is of practical importance because of its relevance to the use of dengue vaccines now under development. It is impossible to prove that clinical manifestations of dengue are not exacerbated by sequential infections. Negative findings can always be countered by arguments that exacerbation occurs only with certain serotypes, only with certain strains of those serotypes, or only when infections occur at critical intervals. Interested persons can examine the relevant data and decide whether the concept of disease exacerbation following sequential dengue infections is myth or reality.