PubMed Health⌕ Search

Biomedical subjects

K P Ober

Publications and source records attributed to K P Ober.

At least 19 recordsLinked to original sources
PubMed1997

The pre-Flexnerian reports: Mark Twain's criticism of medicine in the United States.

By the time Mark Twain was born, in 1835, the political forces of Jacksonian democracy had created an era of unregulated medical practice in the United States. Licensure laws were almost nonexistent, and any citizen could practice medicine. Regular ("allopathic") medicine was competing with at least two dozen other sects, including homeopathic, botanical, and hydropathic medicine. Although allopathy presented itself as the "scientific" branch of medicine and proclaimed the practices of the other sects to be "quackery," its therapies were aggressive and toxic and had no proven advantage over the treatments used by competitors. Through the efforts of the American Medical Association (AMA), allopathic medicine eliminated its competition by promoting the reestablishment of licensure laws in the late 1800s. In a continuation of the same endeavor, the AMA sought to identify weak and inadequate medical schools and commissioned Abraham Flexner to write the famous Flexner report of 1910 (the year of Mark Twain's death). Twain, an insightful political observer and social critic who was familiar with the competing medical systems and the medical politics of the 19th century, questioned the wisdom of limiting patients' medical options. He doubted the competence and intentions of physicians as a group even as he maintained confidence in the abilities of his own physicians. He was critical of the empirical medical practices used during his youth, but he saw hope in the new scientific orientation of medicine in the early 20th century. Twain's commentaries provide a unique perspective on pre-Flexnerian medicine in the United States.

American Medical Association↗
PubMed1996

Ratings of students' performances in a third-year internal medicine clerkship: a comparison between problem-based and lecture-based curricula.

PURPOSE: To compare clinical performances in a third-year medicine clerkship between studies from a problem-based learning (PBL) curriculum and students from a traditional, lecture-based learning (LBL) curriculum. METHOD: The study participants were 88 PBL students and 364 LBL students rotating through a common third-year internal medicine clerkship at the Bowman Gray School of Medicine at Wake Forest University, classes of 1991-1995. Faculty and housestaff assessed the students' performances using four clinical rating scales. The student also completed the medicine student ("shelf") test of the National Board of Medical Examiners (NBME). RESULTS: On average, the PBL students received significantly higher ratings from housestaff and faculty on all four rating scales. No difference in scores on the NBME medicine shelf test was observed. CONCLUSION: The results support the hypothesis that preclinical PBL curricula as found at the Bowman Gray School of Medicine may enhance third-year students' clinical performances.

Achievement↗
PubMed1995

Pheochromocytoma. Update on diagnosis, localization, and management.

Pheochromocytoma, although rare, is associated with a high degree of morbidity and mortality if not recognized. A high degree of suspicion in patients with new-onset hypertension; hypertension with sudden worsening or development of diabetes mellitus; or a family history of MEN, neuroectodermal tumors, or simple pheochromocytoma should prompt biochemical confirmation with either 24-hour urine catecholamines (norepinephrine and epinephrine) or total MET (NMET plus MET). Following confirmation of the diagnosis, radiologic studies with CT and (if needed) MIBG are employed to localize the tumor. Surgical removal is the only definitive therapy. Medical management with alpha-blocking agents, to control symptoms and prevent a hypertensive crisis, is generally advocated for 2 weeks preoperatively and intraoperatively. Occasionally, beta-blockers, employed only after adequate alpha-blockade, are necessary to control tachycardia and tachyarrhythmias. High-dose MIBG and combination chemotherapy have been used adjunctively to treat malignant pheochromocytoma, although neither modality provides lasting satisfactory results. Normal urine assays performed 2 weeks postoperatively ensure the complete removal of all tumor. Additionally, lifelong follow-up (yearly initially) is necessary to detect any signs of benign recurrence or malignancy because these have been reported to occur as long as 41 years after the initial surgical resection. Biochemical evidence of excess catecholamine production usually precedes the clinical manifestations of catecholamine excess when these tumors recur.

Adrenal Gland Neoplasms↗
PubMed1995

The endocrine response to critical illness.

The endocrine response to stress is complex. Elevations in the serum concentrations of the "classic" stress hormones, epinephrine and cortisol, occur following many kinds of physiologic challenge and are accompanied by elevations in corticotropin, GH, and glucagon levels. These changes are probably responsible for the hyperglycemia and hypercatabolism common to most critical illness. If volume depletion is present, vasopressin, renin, and aldosterone secretion are also likely to be stimulated. These hormones, if present in excess, may produce fluid retention and hyponatremia. In some critically ill patients, there is a dissociation of renin and aldosterone production called hyperreninemic hypoaldosteronism, but the clinical importance of this syndrome is poorly understood. Thyroid hormone metabolism is commonly affected by critical illness, which results in characteristic abnormalities of thyroid function testing known as the euthyroid sick syndrome. The reproductive axis is exquisitely sensitive to physiologic stress; hypogonadotropic hypogonadism is a common finding in critical illness. The ongoing challenge to the clinician is to determine whether seemingly abnormal hormone measurements in critically ill patients reflect an appropriate homeostatic response to severe illness or, instead, whether they denote an independent metabolic disorder that might actually cause or contribute to the patient's unstable condition. In view of the exceedingly complex (and poorly understood) interactions involved in the human response to a severe illness, a thoughtful approach to the whole patient is essential and far preferable to indiscriminate hormone testing. Such testing, at best, may be uninterpretable in light of the clinical circumstances or, at worst, may lead to therapeutic misadventures.

Acute Disease↗
PubMed1993

Pituitary apoplexy.

Pituitary apoplexy is a clinical syndrome of headache, visual deficits, ophthalmoplegia, and alteration in mental status resulting from the sudden hemorrhage or infarction of a pituitary adenoma. Infarction of a normal gland also may occur in certain circumstances. Its manifestations are variable, ranging from a clinically benign event to a catastrophic presentation with permanent neurologic deficits or even death. It frequently mimics other intracranial processes and, without a high index of suspicion, may be difficult to diagnose. Radiographic studies, particularly CT and MR imaging, are helpful for diagnosis in both the acute and subacute settings. In its most fulminant presentation, prompt neurosurgical decompression is necessary to preserve sight and life. Corticosteroid replacement is also essential in the acute phase because of the high incidence of adrenal insufficiency. Fortunately, however, with proper management most patients may have good outcomes.

Diagnosis, Differential↗
PubMed1993

Acute adrenal insufficiency.

Acute adrenal insufficiency is a rare disorder associated with high morbidity and mortality if allowed to progress unrecognized. A constellation of nonspecific symptoms including weakness, easy fatigue, nausea, anorexia, and weight loss are typical features of adrenal insufficiency. The index of suspicion should be particularly high if the patient has hyperpigmentation; hyponatremia and/or hyperkalemia; a history of autoimmune disease (hypothyroidism, diabetes) or recent prior use of exogenous steroids or if the patient is on anticoagulant therapy. Any decline in clinical status (hypotension, fever, decreasing mental status), especially in the setting of an acute intercurrent illness, should be treated aggressively, even before laboratory confirmation of the diagnosis. Diagnostic testing is fairly straightforward and readily available. The development of purified synthetic corticosteroid preparations has provided a safe and effective means of replacement. Early awareness, recognition, and intervention remain significant steps in altering the course of acute adrenal insufficiency.

Acute Disease↗
PubMed1992

Thyrotoxic periodic paralysis in the United States. Report of 7 cases and review of the literature.

Although hypokalemic periodic paralysis is a common complication of hyperthyroidism among Asian populations, it is an uncommon problem in the United States. The recent experience in an American medical center with 7 patients with thyrotoxic periodic paralysis (TPP) is reviewed. Compared to most descriptions of this disorder, which tend to reflect the international experience with this disease, patients with TPP in the United States reflect the ethnic makeup of the local population: the predisposition of patients of Asian origin is very evident, but whites are more frequently affected than most previous reports have recognized. Hispanics and American Indians also appear to be at increased risk, and blacks have also been affected. Except for the fact that hyperthyroidism is an absolute requirement for expression of the disease, TPP is identical to familial periodic paralysis (FPP) in its clinical presentation. TPP affects predominantly males (to an even greater degree than FPP), is rarely associated with a positive family history, and has a later onset of presentation than FPP (reflecting the need for hyperthyroidism to occur before the disorder can be expressed). Graves disease is the most common cause of hyperthyroidism in affected patients, but any cause of thyrotoxicosis (including administration of excessive amounts of exogenous thyroid hormone) can trigger attacks of TPP in susceptible subjects. Clinical features of thyroid disease may be very subtle or virtually nonexistent; as a result, thyroid function tests should be routinely monitored in patients with features of hypokalemic paralysis. The pathophysiology of the disorder is not well understood. Definitive treatment of hyperthyroidism leads to cessation of periodic hypokalemic paralysis, but symptoms can return with recurrence of the hyperthyroid condition. Potassium administration during an acute attack will shorten the duration of the episode, and treatment with propranolol, potassium supplementation, or spironolactone may prevent attacks in some patients.

Adult↗
PubMed1991

Endocrine crises. Diabetes insipidus.

Normal water balance with strict maintenance of plasma osmolality depends on appropriate water conservation (controlled by ADH release and action) and additional water intake if required (triggered by the awareness of thirst). Central nervous system pathology (including trauma) commonly involves the hypothalamus and pituitary stalk, leading to impaired osmoreceptor function or diminished ADH production or release, resulting in diabetes insipidus (with potentially life-threatening abnormalities in fluid and electrolyte status). Assessment of the relationships between plasma and urine osmolality and plasma ADH levels will usually lead to an accurate diagnosis. Central diabetes insipidus is effectively treated with replacement of free water deficits and exogenous ADH analogues.

Adult↗
PubMed1990

Postpartum hypopituitarism with preservation of the pituitary-ovarian axis.

An 18-year-old woman developed postpartum hypopituitarism, presenting with personality and behavioral changes caused by severe hypoglycemia. In spite of well-documented deficiencies of thyroxine, cortisol, and growth hormone, she maintained normal ovarian function (reflected by normal menstrual cycles, normal estrogenization on examination, and normal FSH and estradiol levels). Classically, gonadal failure occurs very early in the course of pituitary failure, prior to loss of thyroid or adrenal function; preserved ovarian function is commonly used as clinical evidence of intact pituitary function. This patient emphasizes the importance of pursuing the possibility of pituitary disease in appropriate clinical settings, even in patients with intact ovarian function.

Adolescent↗
PubMed1989

Histiocytosis X of the hypothalamus.

An 18-year-old woman presented with visual disturbance and endocrine dysfunction (diabetes insipidus, delayed puberty, hypothyroidism, hypoadrenalism, and hyperprolactinemia). Computed tomography and enhanced cisternography showed a single hypothalamic mass, which proved at biopsy to be histiocytosis X. Further studies showed the disease to be restricted to the hypothalamus. The patient was treated with hormonal replacement therapy, but her visual acuity continued to worsen. Visual acuity improved after low-dose irradiation of the pituitary fossa and hypothalamus, which also led to disappearance of the mass. This case shows that localized hypothalamic histiocytosis X can be diagnosed and treated successfully before other systems become involved.

Adolescent↗
PubMed1988

Plasma catecholamine levels in patients transported by helicopter for acute myocardial infarction and unstable angina pectoris.

Fourteen patients with either acute myocardial infarction or unstable angina pectoris were transported by helicopter air ambulance to North Carolina Baptist Hospital during a 1-month period. Six patients had preflight and inflight plasma epinephrine and norepinephrine levels determined. All 14 patients were monitored for ventricular arrhythmias. The mean inflight plasma epinephrine level was significantly higher than the mean preflight level (3455 v 841 pg/mL, P less than .005). There was also a trend toward higher inflight norepinephrine levels; however, this increase was not statistically significant. No patient had a monitored ventricular arrhythmia. These findings suggest that helicopter transport of cardiac patients may be associated with significant patient stress, as reflected by high inflight catecholamine levels. Further study with a larger population of patients is needed to determine whether or not an increased incidence of inflight ventricular arrhythmias is associated with these catecholamine changes.

Aged↗
PubMed1988

Radioiodide imaging of struma cordis.

This is the first reported case in which struma cordis was demonstrated with radionuclide imaging. A 56-year-old white woman underwent surgical excision of a benign intracardiac thyroid mass (struma cordis). Subsequent radionuclide imaging with I-123 sodium iodide and Tc-99m labeled red blood cells demonstrated a normal cervical thyroid gland as well as a focus of activity in the mediastinum consistent with intracardiac thyroid.

Choristoma↗
PubMed1988

Return of gonadal function with resection of nonfunctioning pituitary adenoma.

A 42-year-old man with severe testicular failure (testosterone 24 ng/dl, normal 300-1100) was found to have a nonfunctioning chromophobe pituitary adenoma. Resection of the pituitary tumor resulted in recovery of gonadal function (testosterone 359 ng/dl). Hypogonadism caused by pituitary adenomas is usually attributed to either hyperprolactinemia or irreversible destruction of normal pituitary tissue, neither of which is applicable to this patient. The recovery of our patient's gonadal function after operation suggests that a reversible compression of viable tissue or impairment of hypothalamic-pituitary communications was responsible for his endocrine deficiency.

Adenoma, Chromophobe↗
PubMed1987

Thyrotoxicosis caused by functioning metastatic thyroid carcinoma. A rare and elusive cause of hyperthyroidism with low radioactive iodine uptake.

A patient with progressively worsening thyrotoxicosis, refractory to medical therapy, is described. Repeated measurements of thyroidal RAI uptake over a 13 month period were low consistently and could not be explained by iodine ingestion, thyroiditis, or administration of exogenous thyroid hormone. An I-131 scan ultimately revealed striking activity at the base of the skull, reflecting ectopic excessive production of thyroid hormone by a solitary functioning metastatic thyroid carcinoma. The thyrotoxic state resolved after large doses of therapeutic I-131. Typical features of this rare cause of hyperthyroidism are discussed.

Adenoma↗