PubMed HealthSearch

SEARCH · PubMed Health

Results for “unknown etiology”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

The HLA antigens in women with recurrent abnormal pregnancies of unknown etiology.

Women with recurrent abnormal pregnancies of unknown etiology--as compared with those with recurrent abnormal pregnancies of known etiology and with normal controls--had a significantly increased frequency of antigen HLA--A9 (corr. P less than 0.01). Analysis of the frequencies in matings performed at different levels of HLA incompatibility between parents in 35 couples with recurrent abnormal pregnancies of unknown etiology revealed a high degree of wife husband compatibility of the antigens of the HLA--A locus, but not of the antigens of the HLA--B locus. These results indicate that the HLA chromosomal region may influence the reproductive efficiency and the fate of the fetus.

Abortion, Spontaneous

A methodology for establishing a diagnostic index for syndromes of unknown etiology.

A method has been developed to test for heterogeneity in syndromes of unknown etiology and to distinguish between patients with and without the syndrome. The validity of the method was tested on a group of patients suspected of having a syndrome that can be diagnosed by other means (Down syndrome), and was found to be effective. The method was then applied to a group of patients suspected of having a syndrome of unknown etiology (de Lange). It was shown that the group appears to be heterogeneous. A preliminary diagnosis of having or not having the syndrome was made in about 80% of the patients.

Cephalometry

Development of hepatic angiosarcoma in man induced by vinyl chloride, thorotrast, and arsenic. Comparison with cases of unknown etiology.

Examples of human angiosarcoma following exposure to vinyl chloride, Thorotrast, or arsenic (medicinal and industrial) and cases, including children, of unknown etiology were studied to establish diagnostic criteria and to study their evolution. The uniform evolution suggests an environmental factor also in the cases of unknown etiology, which may be established by epidemiologic studies. A precursor stage is charaterized by areas of combined hyperlasia of hepatocytes and a variety of sinusoidal and perisinusoidal cells associated with excess of reticulin and with sinusoidal dialation. The diagnostically useful picture in silver impregnations indicated reticulum formation by the perisinusoidal cells, presumably the libocytes. The hepatocytic proliferation suggests a hepatocarcinogenic but usually not fully expressed potential. The mixed hyperplasia of the various sinusoidal cells proceeds to an overgrowth of angiosarcoma cells, presumably derived from endothelial cells. In early stages they are usually in contact with hepatocytes (intralobular growth). A trabecular arrangement results from loosening of the lobular plate arrangement by dilatation of sinusoids, leading to primary peliosis. With disappearance of the hepatocytes, various growth patterns develop, terminating in nodular, solid angiosarcoma composed of either spindle-shaped or polyhedral cells which undergo necrosis or hemorrhage (secondary peliosis). The interaction between hepatocytes and sinusoidal cells requires elucidation.

Adolescent

Significance of tartrazine sensitivity in chronic urticaria of unknown etiology.

Of 38 patients with chronic urticaria of unknown etiology who were evaluated for food and drug additive sensitivity, 53% (20/38) had urticaria for 1 yr or more. Total eosinophil counts were not elevated in most patients, and the frequency of atopy was found to be similar to that in a general population. Of these 38 patients, 10 (26%) had a personal history of aspirin intolerance, but elimination of aspirin did not relieve the urticaria. In a double-blind crossover challenge with 0.22 mg of tartrazine and a control, tartrazine sensitivity was found in 8% (3/38) of patients with chronic urticaria and 20% (2/10) of patients with aspirin intolerance.

Adult

D-Glucaric acid excretion in newborns with severe jaundice of unknown etiology and due to glucose-6-phosphate dehydrogenase deficiency in Greece.

The urinary D-glucaric acid of 86 full-term newborns was determined on the 10th day of life. Of these, 28 had jaundice due to glucose-6-phosphate dehydrogenase (G-6-PD) deficiency, 24 jaundice of unknown etiology and 18 Rhesus incompatibility. Practically all the cases of the first two groups had a greatly decreased D-glucaric acid excretion whereas this was not a constant finding in the 18 cases with Rh-incompatibility. Normal values were found in 16 healthy controls of the same age. These findings suggest that in severe neonatal jaundice due to G-6-PD deficiency and in jaundice of unknown etiology, there is a greatly reduced excretion of endogenously formed D-glucaric acid, due probably to decreased activity of liver enzymes involved in the metabolism of glucuronic acid. This defect probably contributes to the unconjugated hyperbilirubinemia in these newborns.

Adipates

Association of human leukocyte antigen (HLA)-B5 and -BW22-J with hepatic cirrhosis of apparently unknown etiology.

The majority of patients with hepatic cirrhosis in Japan do not have a history of acute hepatitis or alcoholism. Twenty-nine patients with hepatic cirrhosis which were thought as random samples from cirrhotic patients without a history of acute hepatitis or alcoholism were Human Leukocyte Antigen (HLA) typed. Association of HLA-B5 and -BW22-J with hepatic cirrhosis of apparently unknown etiology was found in p less than 0.003, and p less than 0.01, respectively (128 controls). A predisposition linked to HLA-B5 or -BW22-J related gene or genes seems to play a role in the development of hepatic cirrhosis, at least in a substantial part of patients with hepatic cirrhosis of apparently unknown etiology in Japan.

Adult

Application of metagenomic next-generation sequencing in children with pneumonia of unknown etiology.

OBJECTIVE: To investigate the pathogen spectrum and clinical application value of metagenomic next-generation sequencing (mNGS) in lower respiratory tract specimens from children with pneumonia of unknown etiology. METHODS: A retrospective analysis was conducted on children hospitalized in the intensive care unit (ICU) and respiratory department ward of Children's Hospital of Chongqing Medical University from January 2025 to December 2025. All enrolled cases presented negative results for conventional respiratory pathogen tests and received mNGS testing of lower respiratory tract specimens for etiological identification. The mNGS findings and clinical data of the included children were analyzed. RESULTS: A total of 92 children were enrolled, including 54 males and 38 females, with ages ranging from 2 months to 13 years and 8 months. Causative pathogens were detected in 77 cases (83.7%). The clinically adjudicated etiological diagnosis rates of bacteria, viruses, fungi and atypical pathogens were 75.0% (69/92), 37.0% (34/92), 13.0% (12/92) and 5.4% (5/92), respectively. Thirty-eight cases were complicated with polymicrobial infection, among which bacterial-viral infection was predominant, accounting for 23.1% (24/92). Children with immunocompromised conditions exhibited higher incidences of clinically adjudicated bacterial, fungal and polymicrobial infection than immunocompetent patients. The most common clinically confirmed causative pathogens in immunocompromised children were Streptococcus pneumoniae, human cytomegalovirus, Haemophilus influenzae, Stenotrophomonas maltophilia and Enterococcus faecalis. Treatment regimens were adjusted in 58 cases (63.0%) based on mNGS findings, switching to pathogen-targeted anti-infective therapy. CONCLUSION: For pediatric pneumonia with negative conventional etiological tests, mNGS of lower respiratory tract specimens significantly enhances pathogen detection rates, effectively identifies polymicrobial infection and opportunistic pathogens. Immune status serves as a critical stratification factor influencing pathogen spectrum and infection patterns, with immunocompromised children being more susceptible to opportunistic infections. Adjustment of anti-infective regimens based on mNGS results can effectively facilitate personalized anti-infective therapy.

Humans

[Pulmonary arterial hypertension of unknown etiology. Study of the cardiopulmonary function].

Thirty two cases of pulmonary arterial hypertension of unknown etiology (PAH-UE) were studied. The diagnosis was established by exclusion after the results of hemodinamics studies. Ninety percent of cases had severe PAH (100 mmHg). The end diastolic right ventricular pressure was elevated in 46% of cases. The total pulmonary vascular resistance was increased in the order of the 1700 dinas. seg. cm-5. The cardiac index was 3.3 1/m2 with a right ventricular work index of 3.96 K gm min. The total lung capacity (TLC) was normal, with a vital capacity (VC) of 78% of the predicted value. The residual volume was increased. The mean value of the maximal midexpiratory flow rate (MMFR) was 78%. The A-a gradient of O2 was 30 mmHg, with a venous mixture expressed as a percentage ratio of the cardiac output (Qva/Qt) of 26%. The mean paO2 mmHg and the anatomical pulmonary artery to vein shunt (Qs/Qt) was 9%, with a DLco normal. The clinical hemodinamic correlation was in good agreement. Our results suggested that PAH-UE "per se" has effect in pulmonary function changing slight lung mechanics, and in a moderate degree lung gas exchange. The hipoxemia results meanly from V/Q imbalance.

Adolescent

Abdominal pain of unknown etiology.

The influence of age, sex, duration of symptoms, and exploratory laparotomy on prognosis of adult patients with abdominal pain of unknown etiology was assessed in a retrospective review. Patients with incomplete diagnostic evaluation were excluded. Of the sixty-four patients studied, forty-six were female. Lack of improvement of symptoms in the follow-up period was 67% in females and 22% in males (p less than 0.05). Younger patients tended to have higher improvement rates. Of the patients whose duration of symptoms was less than fourteen days, 65% were improved and 25% were subsequently diagnosed, as compared with 14 and 9%, respectively, of those whose symptoms had been present for more than ninety days (p less than 0.05). Laparotomy did not influence rate of improvement and established a diagnosis in only one of twenty-three patients explored. It is concluded that few of these patients are likely to benefit from laparotomy, especially adult females whose symptoms have been present for more than three months.

Abdomen

Parkinsonism following encephalitis of unknown etiology.

The patient, a clinical case of parkinsonism, was a 32-year-old man, born in 1942, long after the prevalence of von Economo's lethargic encephalitis in Japan. Anatomically, the neurons in the substantia nigra of the mid-brain were extensively degenerated, and presented Alzheimer's neurofibrillary tangles. At the same time, melanin pigment was scattered in the tissue and was phagocytized by glia cells. Perivascular cuffing was observed in the frontal lobe, parietal lobe, temporal lobe, hippocampus, and thalamus as well as in the substantia nigra. Neuronophagia was noted in the thalamic nuclei. The present case was believed to have parkinsonism not clinically or pathologically related to von Economo's encephalitis or to Japanese encephalitis, but following a mild encephalitis of unknown etiology.

Adult

Protracted diarrhea of unknown etiology in Israeli soldiers.

Twenty-five Israeli soldiers, seen over a period of five years, suffered from diarrhea lasting from one month to three years. This was accompanied by weight loss and, in some cases, by evidence of malabsorption and/or mild abnormalities in small bowel and rectal biopsies. The etiology of the diarrhea is unknown, since a routine search for parasites or pathogenic bacteria was unrewarding. An infectious etiology is, however, most likely.

Adolescent

Report of a kindred with bone lesions and subcutaneous abscesses of unknown etiology.

This case report concerns a 12-year-old boy who had a 9-year history of mandibular lesions of unknown origin. The mandible showed changes resembling chronic osteomyelitis. The tibia and temporal bone also exhibited radiolucencies. Many subcutaneous abscesses were present. The boy died at the age of 14 years as a result of rupture of the aorta. In his family, there were seven members who had bone lesions and eleven who suffered from skin abscesses.

Abscess

Hypomagnesemia due to renal disease of unknown etiology.

A young man, investigated because of tetanic convulsions and arthritic pains, was shown to have hypomagnesemia, hypermagnesuria, hypokalemia, hypercalciuria, progressive nephrocalcinosis and chondrocalcinosis. In this syndrome, renal function was normal except for the abnormal excretion of electrolytes. Renal sodium conservation was normal. Light and electron microscopic studies of renal biopsy specimens showed the presence of several abnormal tubules. Immunofluorescent staining showed deposits of immunoglobulins in the glomeruli and tubules. Magnesium therapy was started under balance study conditions and resulted in decreased calciuria and complete remission of subjective symptoms. The progression of nephrocalcinosis was halted, and there was some decrease in the intra-articular calcium deposits after two years of continuous oral magnesium therapy. The administration of spironolactone decreased urinary magnesium but did not normalize it, whereas triamterene administration was without effect in this respect. The results of the morphologic and electrolyte balance studies are discussed. The patient was found to exhibit several features which have not been described before in connection with hypomagnesemia of unknown origin.

Adolescent

Pontiac fever. An epidemic of unknown etiology in a health department: I. Clinical and epidemiologic aspects.

In July 1968, an explosive epidemic of acute febrile illness occurred at a county health department facility in Pontiac, Michigan. Illness characterized principally by fever, headache, myalgia, and malaise affected at least 144 persons, including 95 of 100 persons employed in the health department building. The mean incubation period was approximately 36 hours. Illness was self-limited, generally lasting from two to five days. Secondary cases did not occur in family contacts and second attacks did not consistently follow re-exposure in the building. A defective air-conditioning system was implicated as the source and mechanism of spread of the causative factor. However, extensive laboratory and environmental investigations failed to identify the etiologic agent. Since these investigations a bacterium similar to or identical with the agent responsible for Legionnaires' Disease has been isolated from guinea pigs exposed to the Pontiac health department building in 1968 as well as from guinea pigs exposed to water from the evaporative condenser. Paired sera from 32 cases of Pontiac Fever showed seroconversion or diagnostic rises in antibody titers to this bacterium.

Acute Disease

Rapid onset of hand ischemia of unknown etiology: clinical evaluation and follow-up of ten patients.

Ten patients presenting with a history of the acute onset of hand ischemia have undergone detailed clinical, immunologic, and arteriographic evaluation. The disease is characterized by the acute onset of hand ischemia proceeding to fingertip ulceration, in the absence of recognized systemic disease. None of the patients had any evidence of large artery obstruction. Arteriography showed diffuse obstruction of the palmar and digital arteries. No evidence was found in any patient of any systemic disease process associated with small artery obstruction. These patients are suspected of having a previously unreported variant of hypersensitivity angiitis. Patients are left with permanent obstruction of the palmar and digital arteries. Follow-up suggests the disease in non-recurrent and is characterized by progessive clinical improvement associated with the development of collateral circulation. Conservative management of the condition is recommended.

Adolescent