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At least 19 recordsLinked to original sources
PubMed1997

[Natural history of chromoblastomycosis in Madagascar and the Indian Ocean] [Natural history of chromoblastomycosis in Madagascar and the [Natural history of chromoblastomycosis in Madagascar and the Indian Ocean].

The natural history of chromoblastomycosis was studied in Madagascar by analysing the characteristics of 1323 confirmed cases observed since 1955, including 45 patients receiving a new antifungic drug (terbinafine) during a multicentric study organized in 1995. The surveys data, conserved by the histopathology laboratory in the Institut Pasteur of Madagascar during 40 years, permit this retrospective analysis. The description of two ecosystems, one in the North with Fonsecaea pedrosoi evolving in the tropical rainforest and one in the South with Cladophialophora carrionii (41% of the whole sample) isolated in the spiny desert, demonstrates that the deforestation, in order to product charcoal and to build houses, is the primary factor associated with this disease. The epidemiologic (87% of patients are male and 96% are more than 16 years old, with more than 74% of the lesions located on feet and legs), mycologic (62% of the isolated strains belong to the F. pedrosoi species) and therapeutic (low efficiency of thiabendazole in long-term lesions, high efficiency of terbinafine especially on recent lesions and on Cladophialophora-infected patients) aspects of the natural history of chromomycosis confirmed that Madagascar is the most important focus in the world (global prevalence of about 1 for 8500 inhabitants), with few sporadic cases in the other islands of the Indian Ocean (La Reunion, Comoro islands and Mayotte). In the difficult context of Madagascar, the need for a non-specialized laboratory-applicable diagnostic technique that provides infection and species identification led the Institut Pasteur de Madagascar to develop an ELISA-based technique. A large-scale control throughout the country, with the assessment of effective oral chemotherapy with terbinafine, is seen as possible by the authors with the help of the manufacturer.

Antifungal Agents↗
PubMed1989

Adolescent idiopathic scoliosis: prevalence and natural history.

The natural history presented in this chapter applies only to AIS. Other types of scoliosis have their own natural history and associated problems that may significantly affect the ability of the patient to meet the demands of daily life. Increased public awareness and screening clinics have resulted in an increased number of children referred for orthopaedic opinion, less severe curve magnitude at initial detection, and earlier institution of treatment. Treatment of each patient must be individualized, taking into consideration the probability of curve progression based on curve magnitude, skeletal maturity, sexual maturity, and age (Table 6-7). Overdiagnosis and unnecessary treatment must be avoided. As our knowledge of the natural history of AIS expands, treatment decisions can be based on objective rather than subjective data. Any proposed treatment of this condition must have a reasonable chance of altering the natural history in a positive way. The information available on natural history has been accumulated on relatively small groups of patients and the conclusions presented represent generalities. There are probably many "natural histories" for AIS, especially with reference to curve progression; therefore, treatment decisions must be individualized. Long-term results of various treatments for scoliosis must take into consideration the natural history of the disorder.

Adolescent↗
PubMed2000

Quinolone generations: natural history or natural selection?

The quinolones have evolved from antibacterial agents with a limited spectrum of predominantly anti-gram-negative antimicrobial activity and a restricted number of indications to a class of widely used oral (and, in some cases, intravenous) antibiotics with extensive indications for infections caused by many bacterial pathogens in most body tissues and fluids. This evolutionary pattern has arisen through the development of new core and side-chain structures, with associated improvements in activity, pharmacokinetics and tolerability, and through the selection of molecules that remain useful and well tolerated. This review describes the progress of the quinolones from the first to the third (IIIa and IIIb) generations. Special attention is given to gemifloxacin, currently the most developmentally advanced third-generation quinolone, which has enhanced in vitro gram-positive antimicrobial activity and no troublesome adverse drug reactions. Preliminary data indicate that gemifloxacin should prove to be an important addition to the fluoroquinolone class. Further clinical trial data are awaited with interest.

4-Quinolones↗
PubMed1993

The natural history of amyotrophic lateral sclerosis and the use of natural history controls in therapeutic trials.

We analyzed the natural history of amyotrophic lateral sclerosis in 277 patients. Our goal was to develop a better understanding of the clinical disease and thus improve the design of therapeutic trials. The Tufts Quantitative Neuromuscular Exam (TQNE) was used as the primary assessment instrument. Our analysis suggested that although more observations are desirable, six monthly TQNEs were adequate to establish the rate of disease progression. We observed a spectrum of deterioration rates without definable subgroups. The striking linearity of deterioration was confirmed. We found a high correlation between deterioration rates in arm and leg strength for individual patients, but a wide range between different patients. Sex and the age at clinical onset did not affect the deterioration rate. As compared with patients without a positive family history, those with other affected family members had a slower loss in arm but not leg strength. We propose that natural history controls can be used effectively in the design of ALS therapeutic trials.

Adult↗
PubMed1993

Superficial bladder carcinoma. Factors affecting the natural history.

The natural history of superficial bladder carcinoma has an important bearing on the outcome of response to intravesical chemotherapy or immunotherapy. It may vary in different parts of the world, but it is essential that urologists know within their own practice how tumours respond to the initial transurethral resection. Many factors influence the natural history of superficial bladder carcinoma, and some, such as poor-grade, large tumour at presentation, smoking history, poor response to initial resection, and dysplasia or carcinoma in situ, should alert the urologist to introduce intravesical therapy at an early stage.

Administration, Intravesical↗
PubMed1983

Unoperated abdominal aortic aneurysm: presentation and natural history.

The natural history of abdominal aortic aneurysm (AAA) is death from rupture unless the patient dies from another cause prior to rupture. Elective aortic grafting is the treatment of choice. Following rupture, emergency operation is the only treatment which will prolong the patient's survival. Controversy still exists as to the optimum management in poor risk patients and in those with a small aneurysm. This paper describes the presentation and natural history of 65 patients presenting with a ruptured abdominal aortic aneurysm who did not have an emergency operation, and a further 27 patients in whom the diagnosis of intact AAA was made who did not have an elective aortic replacement graft. The correct diagnosis was made at the time of admission in only 43 of the 65 patients with ruptured aneurysms. The diagnostic errors and appropriate investigations in cases of doubt are discussed. The mean time from admission to hospital to death was 8 hours. The reasons for not performing an elective operation in the 27 patients known to have AAA are given. Nine have subsequently died from rupture. There have been 7 deaths from other causes.

Aged↗
PubMed1999

The natural history of multiple sclerosis: a geographically based study. 5. The clinical features and natural history of primary progressive multiple sclerosis.

We report a natural history study of 216 patients with primary progressive (PP)- multiple sclerosis defined by at least 1 year of exacerbation-free progression at onset. This represents 19.8% of a largely population-based patient cohort having a mean longitudinal follow-up of 23 years. This subgroup of PP-multiple sclerosis patients had a mean age of onset of 38.5 years, with females predominating by a ratio of 1.3:1.0. The rate of deterioration from disease onset was substantially more rapid than for relapsing-remitting multiple sclerosis, with a median time to disability status score (DSS) 6 and DSS 8 of 8 and 18 years, respectively. Forty-nine percent of patients were followed through to death. Examination of the early disease course revealed two groups with adverse prognostic profiles. Firstly, a shorter time to reach DSS 3 from onset of PP-multiple sclerosis significantly adversely influenced time to DSS 8. Second, involvement of three or more neurological systems at onset resulted in a median time to DSS 10 of 13.5 years in contrast to PP-multiple sclerosis patients with one system involved at onset where median time to death from multiple sclerosis was 33.2 years. However, age, gender and type of neurological system involved at onset appeared to have little influence on prognosis. Life expectancy, cause of mortality and familial history profile were similar in PP-multiple sclerosis and non-PP-multiple sclerosis (all other multiple sclerosis patients from the total population). From clinical onset, rate of progression was faster in the PP-multiple sclerosis group than in the secondary progressive (SP)-multiple sclerosis group. When the rates of progression from onset of the progressive phase to DSS 6, 8 and 10 were compared, SP-multiple sclerosis had a more rapid progressive phase. A substantial minority (28%) of the PP-multiple sclerosis cohort had a distinct relapse even decades after onset of progressive deterioration. These studies establish natural history outcomes for the subgroup of multiple sclerosis patients with primary progressive disease.

Adult↗
PubMed1986

[Subarachnoid hemorrhage due to aneurysm. Natural history].

The natural history represents a basic reference point for evaluating temporal profile of a disease as well as the effect of the employed therapy. The incidence and the risk factors of the subarachnoid hemorrhage due to single aneurysm are presented. In particular the survival rate and mortality are evaluated in conservative treated group versus radical surgery group. The most relevant factors that affect survival are: time and clinical grades of severity. The best chance of alternating overall mortality from subarachnoid hemorrhage due to aneurysm seems to be: surgery within 1-2 days or secondary prevention.

Adolescent↗
PubMed1998

A longitudinal study of patients with venous malformations: documentation of a negligible hemorrhage risk and benign natural history.

BACKGROUND: The natural history of cerebral venous malformations has not been well documented, and the clinical significance of these common lesions remains controversial. OBJECTIVE: The objective of this study was to follow longitudinally the clinical course of patients with cerebral venous malformations to document the natural history of the lesion. METHODS: Ninety-two patients with radiographically confirmed venous malformations were entered into the study between 1987 and 1996. Annual follow-up was maintained by clinic visits and/or phone interviews. Sixty-three patients (25 men and 38 women) with more than 1 year of follow-up were analyzed. McNemar's test and logistic regression analysis was applied to prevalence of presenting symptoms over time. An average per patient follow-up of 4.2 years yielded 2,721 retrospective and 301 prospective lesion-years for analysis. RESULTS: Average age at diagnosis was 39.1 years (SD, 18.7 years; range, 2 to 73 years). The most frequent lesion locations included the frontal lobe (55.6%, n=35) and the cerebellum (27%, n=17). The most frequent presentations included headache (50.8%, n=32), focal neurologic deficits (39.7%, n=25), and seizure (30.2%, n=19). Prevalence of headache (p=0.048) and seizure (p=0.016) decreased over time without treatment of the lesion. A second cerebrovascular lesion was identified in 12 patients (19%). Two patients had a symptomatic intracerebral hemorrhage attributable to their venous malformation. Risk of hemorrhage was 0.15% per lesion-year (95% CI, 0.06 to 0.38%). CONCLUSIONS: This study establishes that the natural history of venous malformations is benign, that the risk of hemorrhage from these lesions is negligible, and that conservative therapy is warranted.

Adolescent↗
PubMed1999

The natural history of breast cancer.

The natural history of breast cancer has not been fully elucidated, but physicians are making progress in the treatment of patients with this disease. Randomized, controlled trials indicate that screening, adjuvant systemic therapy, and adjuvant radiotherapy can reduce the risk for death caused by breast cancer. More importantly, national statistics show that breast cancer death rates are now decreasing (after remaining stagnant for nearly 40 years), but additional investigation into the natural history of breast cancer is clearly warranted. The randomized controlled trials on screening and local therapy, in particular, provide important insights into the natural history of the disease. Thus, the results of these trials should serve as a basis for additional investigation. Ultimately, a better understanding of the natural history of breast cancer may translate into improved treatments and better outcomes.

Breast Neoplasms↗
PubMed2000

Natural history and the Encyclopedie.

The general popularity of natural history in the eighteenth century is mirrored in the frequency and importance of the more than 4,500 articles on natural history in the Encyclopedie. The main contributors to natural history were Daubenton, Diderot, Jaucourt and d'Holbach, but some of the key animating principles derive from Buffon, who wrote nothing specifically for the Encyclopedie. Still, a number of articles reflect his thinking, especially his antipathy toward Linnaeus. There was in principle a natural tie between encyclopedism, with its emphasis on connected knowledge, and the task of natural historians who concentrated on the relationships among living forms. Both the encyclopedists and the natural historians aimed at a sweeping overview of knowledge, and we see that Diderot's discussions of the encyclopedia were apparently informed by his reading of natural history. Most of the articles on natural history drew from traditional sources, but there are differences in emphasis and choice of subject, depending upon the author. Diderot's 300 contributions are often practical, interesting, and depend upon accounts from other parts of the world. Jaucourt, who wrote more articles on natural history than anyone else, followed in his foodsteps. Daubenton's 900 articles reflected a more narrow, professional approach. His contributions concluded for the most part with Volume 8, and Jaucourt carried on almost single-handedly after that. While staking out traditional ground (description, taxonomy) and advancing newer theoretical views linked with Buffon, natural history in the Encyclopedie avoided almost completely the sentimentalism concerning nature that developed after Rousseau.

Encyclopedias as Topic↗
PubMed1999

[Clinical presentation and natural history of endometriosis].

Natural history of endometriosis is unpredictable. Some recent data show that endometriosis is a progressive disease. Minimal lesions are transient and peritoneal implants are reorganized continuously. So, minimal endometriosis could be considered like a transient statement close to physiology. In favourable statement such as the decreased activation of NK cells, the variable secretions of cytokines, pelvic macrophages and growth factors, the peritoneal implants evoluted like a progressive disease until severe endometriosis. Endometriosis is a frequent cause of pelvic pain with dysmenorrhea, dyspareunia, chronic pelvic pain and infertility. The diagnosis can be suspected by a clinical examination preferentially during menstruation with fixed uterine retroversion peritoneal infiltration, retraction of the rectum and retrovaginal endometriosis, and adnexal cyst.

Adnexal Diseases↗