The use of ketoconazole as an inhibitor of steroid production

The relationship of endogenous cortisol to psychiatric disorder: a review

OBJECTIVES

To focus on hypothalamic-pituitary-adrenal (HPA) axis activity, especially endogenous hypercortisolemia, to study its role in the maintenance of psychiatric illness, and to entertain the probability that the elderly are vulnerable.

METHOD

Case presentation, clinical and research literature review, and theoretical discussion.

RESULTS

Clinical and research evidence overwhelmingly suggest that hypercortisolemia is toxic to the hippocampus. Some research supports the position that it can be a treatable perpetuating factor in a subset of affective disorders and psychoses. Pharmacological treatments to correct hypercortisolemia have been used by endocrinologists. Hypercortisolemic treatment-resistant and nontreatment-resistant psychoses and affective disorders have been successfully treated by a small number of researchers who remain interested in this subject. Data pertaining to geriatric psychoses may be germane but are sparse.

CONCLUSIONS

It behooves us to research diagnostic methods pertaining to psychoses and affective disorders associated with hypercortisolemic states. Very little research is available, but we must be alert to the possibility that the elderly are more susceptible to cortisol endotoxicosis than the younger adult population. Without accurate diagnosis, we cannot take advantage of existing antiglucocorticoid strategies.

A neuroendocrine role in cocaine reinforcement

Cocaine stimulates the secretion of corticosterone and ACTH, probably through a CRF-related mechanism, indicating that the drug activates the HPA axis. Indeed, cocaine has been reported to produce anxiety and to precipitate episodes of panic attack during chronic use and withdrawal in humans and to induce anxiogenic behavior in animals. Cocaine also alters benzodiazepine receptor binding in discrete regions of the rat brain. Some of these changes in binding are obviously related to the convulsions and seizures which are often observed in an acute cocaine overdose. However, data from behavioral studies have suggested that some of these effects may be related directly to cocaine reinforcement since receptor changes also were observed when binding in the brains of rats that self-administered cocaine was compared with that from animals that had received identical yoked, but non-contingent infusions of the drug. In this regard, pretreatment with the benzodiazepine receptor agonists chlordiazepoxide and alprazolam decreased cocaine self-administration without decreasing food-reinforced responding, suggesting that these effects were specific for cocaine. Since this attenuation of self-administration was reversed by increasing the unit dose of cocaine, it is likely that these drugs were decreasing cocaine reinforcement. In contrast, exposure to stress increases vulnerability to self-administer psychostimulants. In these experiments, low-dose cocaine self-administration was related directly to stress-induced increases in plasma corticosterone, such that plasma corticosterone was always greater than 150 ng/ml for rats which subsequently self-administered cocaine at doses of 0.125 mg/kg/infusion or lower, suggesting a threshold for the hormone in cocaine reinforcement. In other experiments, bilateral adrenalectomy completely abolished the acquisition of intravenous cocaine self-administration in naive rats, while metyrapone decreased ongoing self-administration. In addition, ketoconazole pretreatment resulted in patterns of self-administration that were virtually indistinguishable from that observed during saline extinction, suggesting that plasma corticosterone is not only important, but may even be necessary for cocaine reinforcement. The mechanisms through which adrenocorticosteroids alter cocaine reinforcement remain to be determined, but there is increasing evidence that the mesocorticolimbic dopaminergic system is involved. In particular, the medial prefrontal cortex appears to be at least one brain region where dopamine and adrenocorticosteroids may interact to affect cocaine reinforcement.

Endocrinologic complications of HIV infection

A variety of endocrine disorders occur in HIV-infected patients. The abnormalities may be a consequence of HIV infection, or may result from opportunistic infections, associated malignancies, illness-associated cytokine production, or use of therapeutic agents. Observations and controversies concerning adrenal, gonadal, thyroidal, and metabolic abnormalities are discussed. Heightened awareness of problems that might otherwise be overlooked will permit timely diagnosis and treatment of identified problems, which will enhance and potentially prolong the lives of people infected with HIV.

Low dose ketoconazole is an effective and a relatively safe alternative in the treatment of hirsutism

Efficacy, clinical and hormonal effect of ketoconazole in 400 mg/day dose was tested in a prospectively-designed study. Twenty four patients with hirsutism according to the Ferriman and Gallwey score (> 8) and elevated blood androgen levels were administered 400 mg/day ketoconazole for 6 months. Basal and posttherapy early follicular phase androgens and biochemical parameters were evaluated. In 22 patients significant improvement and in 2 slight improvement was seen in subjective complaints. No side-effects were observed in these patients other than 2 cases of pruritus (transient), 2 mild gastric upset and 1 mastodynia. All patients completed the study. Low dose ketoconazole seems to be effective in the treatment of hirsutism with relatively few side-effects but still should be reserved as an alternative choice due to the potential for deleterious hepatic effects.

Endocrine implications of human immunodeficiency virus infection

Endocrine abnormalities occur frequently in HIV-infected patients. Although the majority of endocrine disorders reflect chronic infection, stress, and malnutrition, some disorders are characteristic of HIV infection or AIDS and deserve particular clinical attention. Identification of HIV patients at risk of frank endocrine disorders, rapid and correct diagnosis, and appropriate management are essential steps to minimize morbidity and mortality. Finally, increasing evidence from in vitro studies suggests that various hormones may influence HIV replication as well as the course of HIV disease and associated disorders. Future studies on the molecular mechanisms of hormones on HIV action and clinical studies on the effects of hormones as adjunctives to established forms of therapy may stimulate development of novel therapeutic strategies that will benefit HIV-infected patients.

The influence of cortisol on spontaneous and 5HT stimulated prolactin release in man

The role of cortisol in influencing spontaneous and 5HT mediated prolactin release was investigated in 17 healthy male subjects who took part in 3 separate studies. Five of the subjects were treated for 24 h with metyrapone (the 11 beta-hydroxylase inhibitor which prevents the conversion of 11-deoxycortisol to cortisol) on one occasion and placebo for 24 h on another. On both test occasions their spontaneous prolactin was monitored before they underwent serotonergic-stimulated prolactin release using D-fenfluramine (30 mg). Treatment with metyrapone enhanced the spontaneous nocturnal prolactin surge and also the prolactin response to D-fenfluramine. Six of the subjects were treated for 24 h with hydrocortisone on one occasion or placebo on the other. With hydrocortisone treatment no nocturnal increase in prolactin was observed and the response to D-fenfluramine challenge was attenuated. To determine whether the influence of cortisol on prolactin release is at a pituitary or supra-pituitary site 6 subjects were tested with thyrotropin releasing hormone (TRH) which acts directly on the pituitary to bring about prolactin release. They were each tested twice, following either metyrapone or placebo treatment. The rise following metyrapone was significantly greater than that seen following placebo. The results suggest that cortisol influences both spontaneous and 5HT stimulated PRL release, probably acting at a pituitary level.

Azalanstat (RS-21607), a lanosterol 14 alpha-demethylase inhibitor with cholesterol-lowering activity

Agents that inhibit hepatic cholesterol biosynthesis reduce circulating cholesterol levels in experimental animals and humans, and may be of pharmacological importance in the prevention of atherosclerosis. Azalanstat (RS-21607), a synthetic imidazole, has been shown to inhibit cholesterol synthesis in HepG2 cells, human fibroblasts, hamster hepatocytes and hamster liver, by inhibiting the cytochrome P450 enzyme lanosterol 14 alpha-demethylase. When administered orally to hamsters fed regular chow, RS-21607 (50 mg/kg/day) lowered serum cholesterol in a dose-dependent manner (ED50 = 62 mg/kg) in a period of 1 week. It preferentially lowered low density lipoprotein (LDL) cholesterol and apo B relative to high density lipoprotein (HDL) cholesterol and apo A-1. It also lowered plasma cholesterol levels in hamsters fed a high saturated fat and cholesterol diet. RS-21607 inhibited hepatic microsomal hydroxymethylglutaryl-CoA (HMG-CoA) reductase activity in hamsters in a dose-dependent manner (ED50 = 31 mg/kg), and this was highly correlated with serum cholesterol lowering (r = 0.97). Cholesterol lowering by azalanstat and cholestyramine was additive, and the increase in HMG-CoA reductase brought about by cholestyramine was attenuated significantly by azalanstat. In vitro studies with HepG2 cells indicated that this modulation of reductase activity was indirect, occurring at a post-transcriptional step, and it is proposed that a regulatory oxysterol derived from dihydrolanosterol (or lanosterol) may be responsible for this regulation. Azalanstat does not appear to lower circulating cholesterol in the hamster by up-regulation of the hepatic LDL receptor, suggesting that other mechanisms are involved. Orally administered azalanstat (50-75 mg/kg) stimulated hepatic microsomal cholesterol 7 alpha-hydroxylase activity by 50-400% in hamsters, and it is postulated that this may result from modified cholesterol absorption and bile acid synthesis.

The psychotropic effects of inhibitors of steroid biosynthesis in depressed patients refractory to treatment

Twenty patients, diagnosed as suffering from treatment-resistant major depression, were treated with one or more drugs that decrease corticosteroid biosynthesis. Nine were psychotic, 11 nonpsychotic. Seventeen completed the treatment (8 psychotic, 9 nonpsychotic); 13 responded (5 psychotic, 8 nonpsychotic; 11 responded completely (i.e., a drop in the Hamilton Depression Scale of at least 50%, to < or = 15), and 2 responded partially. The mean age of the responders (45.2 +/- 12.6 years) did not differ significantly from that of the nonresponders (48.7 +/- 12/3). Data were analyzed in the following categories; (1) the presence or absence of psychosis, (2) response or nonresponse to treatment, and (3) the drug(s) used (aminoglutethimide, ketoconazole, or a combination of either of these with metyrapone). The patients improved over time on the Hamilton Depression Scale independent of the medication used. Responders demonstrated improvement in mood, insomnia, anxiety, diurnal variation, paranoia and obsessive compulsiveness. Nonpsychotics responded better than psychotics.

Differential diagnosis in cushing syndrome. Use of corticotropin-releasing hormone

Testing with ovine corticotropin-releasing hormone (CRH) has facilitated the differential diagnosis of Cushing syndrome, which is often not straightforward. We provide our experience between January 1989 and August 1993 with 30 patients with Cushing syndrome and describe 4 cases in detail to illustrate how CRH testing can be successfully applied to some of the difficulties encountered in the evaluation. CRH testing proved to be particularly useful in distinguishing cases of Cushing syndrome of adrenal etiology from those of Cushing disease with low or undetectable adrenocorticotropin (ACTH) levels. CRH testing during petrosal sinus sampling was also found to help distinguish the ectopic ACTH syndrome from pituitary-dependent Cushing syndrome. Our cases illustrate the need for careful biochemical evaluation before proceeding to imaging studies. Using CRH testing to evaluate cases of Cushing syndrome in which standard testing was inconclusive can provide useful information and lead to a more rapid determination of etiology and definitive therapy than previously possible.

Ketoconazole and sulphaphenazole as the respective selective inhibitors of P4503A and 2C9

1. The potential of ketoconazole and sulphaphenazole to inhibit specific P450 enzyme activities (1A2, 2A6, 2B6, 2C9/8, 2C19, 2D6, 2E1, 3A and 4A) was investigated using human liver microsomes. 2. Ketoconazole demonstrated an inhibitory effect on cyclosporine oxidase and testosterone 6 beta-hydroxylase activities, with mean IC50's of 0.19 and 0.22 microM respectively. Ketoconazole inhibition of the other P450 activities investigated was significantly less, as illustrated by IC50's of at least a magnitude higher. 3. Sulphaphenazole was shown to have an inhibitory effect on tolbutamide hydroxylase activity, with a mean IC50 of 0.8 microM in incubations containing 100 microM tolbutamide. Sulphaphenazole (at concentrations of up to 100 microM) did not exhibit any significant inhibition of the other enzyme activities investigated. 4. Ketoconazole and sulphaphenazole are the respective selective inhibitors of P4503A and 2C9. Ketoconazole at 1 microM and sulphaphenazole at 10 microM can be used to establish the involvement of P4503A and 2C9 respectively in oxidative reactions in human liver microsomes.

Ketoconazole for prevention of postoperative penile erection

OBJECTIVES

To determine if ketoconazole, an inhibitor of testosterone synthesis, can prevent postoperative spontaneous erections in patients undergoing penile surgery.

METHODS

Ketoconazole was administered to 8 patients, aged 14 to 42 years, who underwent penile surgery. All patients received ketoconazole 400 mg orally three times daily starting on the day of surgery. Liver function tests were obtained preoperatively and after the completion of treatment.

RESULTS

Ketoconazole successfully prevented erections in all patients. None of the patients demonstrated liver function abnormalities.

CONCLUSIONS

Ketoconazole is a reliable method to prevent postoperative penile erection. With the proper monitoring of liver function tests and the avoidance of drug interactions, ketoconazole therapy also appears to be safe.

P450 inhibitors of use in medical treatment: focus on mechanisms of action

A number of cytochrome P450s are targets for compounds that are clinically used or under clinical evaluation for treatment of patients with mycotic infections, such as dermatophytosis, superficial and systemic candidiasis, cryptococcosis and aspergillosis, with skin diseases, such as psoriasis or ichthyosis, and other retinoid-sensitive malignancies, e.g., neuro-ectodermal glioma. Some of the P450 inhibitors are candidates for the treatment of hirsutism or prostate cancer, others are potent inhibitors of the P450 isomerase involved in the synthesis of thromboxane A2, a potent platelet aggregation inducer and vasoconstrictor.

Long-term itraconazole prophylaxis against Aspergillus infections in thirty-two patients with chronic granulomatous disease

We conducted a prospective, open study of oral itraconazole therapy (5 and then 10 mg/kg per day) to assess tolerance and potential efficacy in preventing fungal infections in patients with chronic granulomatous disease. Thirty-two patients were enrolled in one center between 1985 and 1991. Tolerance was excellent in all cases. Poor compliance was suspected in three cases. Two patients were excluded from efficacy analysis because itraconazole was used as part of therapy for pulmonary aspergillosis. Of 30 patients, 3 developed a fungal (Aspergillus) lung infection, an incidence 3.4/100 patient-years versus 11.5 in a historical control group that did not receive any prophylaxis (p = 0.13) and 9.55 in a historical group of patients who received daily ketoconazole prophylaxis (p = 0.19). The percentage of patients infected with Aspergillus was significantly different: 10% in the itraconazole group versus 34.4% in the untreated group (p = 0.013). These results require further evaluation through a comparative randomized trial to assess the possible benefit of itraconazole prophylaxis in patients with chronic granulomatous disease.

Lowering cortisol enhances growth hormone response to growth hormone releasing hormone in healthy subjects

Cortisol is known to influence growth hormone release probably by modulating somatostatin tone. We examined the effect of metyrapone (the 11 beta-hydroxylase inhibitor) treatment on growth hormone response to growth hormone releasing hormone (1 microgram kg-1 body wt). Six healthy male subjects were tested on two occasions 1 wk apart. On one occasion they received metyrapone followed by growth hormone releasing hormone and on the other placebo followed by growth hormone releasing hormone. In all subjects metyrapone produced a significant drop in cortisol levels. Together with this drop there was a significant enhancement of growth hormone response to growth hormone releasing hormone. The GH response was negatively correlated with the cortisol level. Growth hormone release in response to growth hormone releasing hormone challenge is thus seen to be heavily influenced by cortisol levels.

Role of bilateral adrenalectomy in Cushing's disease

Of 206 patients with Cushing's syndrome observed from 1975 through 1991, 144 (69.9%) had pituitary-dependent Cushing's disease. Of the 110 patients who underwent pituitary surgery, 31 (28%) developed an early recurrence and 23 patients (20%) had a late relapse 1 to 5 years after primary pituitary exploration. We performed a one- or two-step total bilateral adrenalectomy in 43 patients-9 men and 34 (79.4%) women, with an average age of 47.5 years (range 13-58 years). Thirty-three of these patients had already been treated by previous transsphenoidal surgery or alternatively by external pituitary irradiation over a period of 1 to 10 years prior to adrenal surgery. Thirty-one patients underwent adrenalectomy by a double lumbar access or left lumbar and right subcostal incisions. In our series of 55 operations, perioperative complications included two splenectomies and two hemorrhages (7.3%). The early mortality rate was 3.6% (two patients). Minor complications consisted of wound infection (13.5%), bronchopneumonia or pneumothorax (four cases) with a 7- to 12-day longer hospital stay. Nelson syndrome occurred in 6 of 41 patients (14.6%). We therefore believe that bilateral adrenalectomy does play a major role in the treatment of patients with pituitary-dependent Cushing's disease unsuccessfully managed by transphenoidal surgery. It represents the definitive therapy for those patients in whom hypophysectomy was not able to provide satisfactory control of the disease.

Low dose ketoconazole attenuates serum androgen levels in patients with polycystic ovary syndrome and inhibits ovarian steroidogenesis in vitro

OBJECTIVE

To investigate the effects of a low-dose ketoconazole on ovarian steroidogenesis and on serum androgen levels in polycystic ovary syndrome (PCOS).

DESIGN

In vitro, human granulosa-luteal cells were incubated with ketoconazole and radiolabeled steroid substrates, to follow their metabolic fate by thin-layer chromatography analysis. In vivo, normally cycling women (n = 7) in their luteal phase were administered one tablet of 200 mg ketoconazole at 8 A.M. Serum steroid levels, sampled basally and at 12 P.M., 4 P.M., and 8 A.M. the next morning, were compared with untreated control group (n = 7) values. Polycystic ovary syndrome women (n = 11) were similarly administered ketoconazole 6 to 10 days after occurrence of spontaneous menses. Adrenal origin of hyperandrogenemia was excluded by stimulation with ACTH and a normal basal DHEAS. The steroid diurnal variation was determined in the same patients a day before treatment.

RESULTS

In vitro, ketoconazole selectively inhibited the key steroidogenic cytochromes, namely P450scc, P45017 alpha, and P450arom (IC50 = 0.5 to 1.0 microgram/mL). In vivo, in the luteal phase, ketoconazole transiently decreased serum values (mean +/- SE) of E2 (19.2% +/- 2.1%) and P (38.3% +/- 8.5%) within 4 to 8 hours. The same low-dose ketoconazole, administered to PCOS women, decreased serum values of androstenedione (17.6% +/- 4.7%), T (24.6% +/- 7.6%), and free T (30.7% +/- 7.7%). In contrast, 17 alpha-hydroxyprogesterone increased concomitantly (78.5% +/- 10.8%), suggesting a greater suppressibility of the P45017 alpha lyase activity. The E2 levels in PCOS patients were slightly elevated (29.1% +/- 5.6%), resulting in a 1.7- to 2.3-fold increase of the E2:T ratio.

CONCLUSIONS

These findings suggest that a low-dose ketoconazole may facilitate a decreased intraovarian T:E2 ratio, which may prove favorable for follicular maturation in PCOS.

Familial testotoxicosis in a Chinese family

We report two cases of 'familial testotoxicosis' in a family of Southern Chinese descent. The proband, an 8-year 4-month-old boy and his 35-year-old father both presented with early sexual development. In both cases the testicular volume was only 6 ml despite fully developed secondary sexual characteristics. Both patients had adult testosterone concentrations but a suppressed gonadotrophin response to gonadotrophin-releasing hormone. The suppressed gonadotrophin response to gonadotrophin-releasing hormone in the father suggests that autonomous gonadal production of sex steroid by the testes can persist well into adult life in some patients with familial testotoxicosis.

Hormonal ablation as effective therapy for carcinomatous meningitis from prostatic carcinoma

BACKGROUND

Metastases to the meninges from prostatic cancer are rare, accounting for less than 0.5% of all solid tumor cases. Management for patients with leptomeningeal metastases of various histologic types includes intrathecal chemotherapy and radiation therapy, but the prognosis is poor. Therefore, the identification of selected patients for whom effective therapy exists is of paramount importance.

METHODS

A patient with adenocarcinoma of the prostate presented with leptomeningeal metastases as his first manifestation of metastatic disease.

RESULTS

Androgen blockade was initiated with flutamide and ketoconazole. After 5 days of therapy, leuprolide acetate depot was substituted for ketoconazole. The patient responded to therapy and remained asymptomatic with a normal serum prostate-specific antigen levels at 16-plus months with no further evidence of malignant cells in spinal fluid from repeated lumbar punctures.

CONCLUSION

Patients with hormone-naive metastatic prostatic carcinoma manifested as carcinomatous meningitis should be considered for hormonal ablative therapy. This is preferred to the use of intrathecal chemotherapy, which has limited efficacy.

Effect of dexamethasone and cytochrome P450 inhibitors on the formation of 7 alpha-hydroxydehydroepiandrosterone by human adipose stromal cells

7 alpha-Hydroxydehydroepiandrosterone (7 alpha-OHDHA) is a major metabolite of dehydroepiandrosterone (DHA) using adipose stromal cells. To gain a better understanding of the factors regulating DHA metabolism, we examined the effect of dexamethasone and cytochrome P450 inhibitors on the formation of 7 alpha-OHDHA. Dexamethasone (10(-9) to 10(-7) M) stimulated 7 alpha-OHDHA formation in a dose-dependent manner with a 2- to 5-fold stimulation at 10(-7) M. The dexamethasone stimulated 7 alpha-OHDHA formation was inhibited by RU486 in a dose-dependent manner with suppression to basal levels at 10(-6) M. Progesterone (10(-7) M) had no effect on 7 alpha-OHDHA formation suggesting that the dexamethasone stimulation was acting through the glucocorticoid receptor. Conversion of DHA to 7 alpha-OHDHA was inhibited by ketoconazole and metyrapone. An inhibition of 70-80% was obtained with ketoconazole and 25-60% with metyrapone at concentrations of 10(-5) M. Aminoglutethimide phosphate was less effective than either ketoconazole or metyrapone in inhibiting 7 alpha-OHDHA formation with < 30% inhibition at 10(-5) M. These studies indicate that 7-hydroxylation provides an alternative pathway for the metabolism of DHA in peripheral tissues. This pathway, which is regulated by glucocorticoids, may influence the amount of DHA available for conversion to androstenedione and its subsequent aromatization to estrone. The biological role of the 7-oxygenated metabolites and their effects on other steroidogenic pathways have not been established.

Ketoconazole effectively reverses multidrug resistance in highly resistant KB cells

The antifungal agent ketoconazole was found to overcome resistance to vinblastine and doxorubicin in multidrug resistant KB-V1 cells in vitro. These cells are several hundred-fold more resistant than the parental cell line KB-3-1. Ketoconazole had little or no effect on the parental KB-3-1 cells. The concentrations used to overcome drug resistance in vitro have already been safely used in vivo for treatment of fungal infections and in the monotherapy of hormone independent prostate carcinomas to block adrenal androgen production. Because of a possible beneficial effect of a combination of ketoconazole and a chemotherapeutic drug in multidrug resistant cancers, we examined a panel of 11 prostate carcinoma tissues for the expression of the MDR1 gene by an RNA-PCR assay. MDR1 expression was detectable, albeit at low levels, in 8 of the 11 tumors, suggesting a possible role of this gene in the drug resistance of prostate carcinomas. Our data suggest that ketoconazole might be useful in overcoming multidrug resistance in concentrations that are achievable in humans.

Oral azole drugs as systemic antifungal therapy

The oral azole drugs--ketoconazole, fluconazole, and itraconazole--represent a major advance in systemic antifungal therapy. Among the three, fluconazole has the most attractive pharmacologic profile, including the capacity to produce high concentrations of active drug in cerebrospinal fluid and urine. Ketoconazole, the first oral azole to be introduced, is less well tolerated than either fluconazole or itraconazole and is associated with more clinically important toxic effects, including hepatitis and inhibition of steroid hormone synthesis. However, ketoconazole is less expensive than fluconazole and itraconazole--an especially important consideration for patients receiving long-term therapy. All three drugs are effective alternatives to amphotericin B and flucytosine as therapy for selected systemic mycoses. Ketoconazole and itraconazole are effective in patients with the chronic, indolent forms of the endemic mycoses, including blastomycosis, coccidioidomycosis, and histoplasmosis; itraconazole is also effective in patients with sporotrichosis. Fluconazole is useful in the common forms of fungal meningitis--namely, coccidioidal and cryptococcal meningitis. In addition, fluconazole is effective for selected patients with serious candida syndromes such as candidemia, and itraconazole is the most effective of the azoles for the treatment of aspergillosis.

Response of hypertension to conventional antihypertensive treatment and/or steroidogenesis inhibitors in Cushing's syndrome

OBJECTIVES

To evaluate the effect of conventional antihypertensive drugs and/or inhibitors of steroid production in the management of hypertension in Cushing's syndrome.

DESIGN

A retrospective open clinical study with pre- and post-treatment assessment.

SETTING

A university hospital, where patients were initially admitted and then followed-up in an ambulatory clinic over a period of 6 years.

SUBJECTS

Forty consecutive hypertensive patients with Cushing's syndrome.

INTERVENTIONS

Patients were divided into two groups according to the different management of hypertension. The first group (group 1) of 28 patients included those treated with antihypertensive drugs at full dose (diuretics, calcium antagonists, angiotensin converting enzyme [ACE] inhibitors, as single agents or in combination). The second group (group 2) of 12 patients received ketoconazole alone.

MAIN OUTCOME MEASURES

Blood pressure variations compared to pre-treatment levels.

RESULTS

Blood pressure normalization was obtained in four of the 28 patients of group 1. In 12 of the remaining patients, ketoconazole, an inhibitor of steroid production, was subsequently added and this normalized blood pressure in all but the one in whom cortisol was not decreased. In the 12 patients of group 2, ketoconazole alone lowered blood pressure within normal limits in all but one who had long-standing hypertension.

CONCLUSIONS

In hypertensive patients with Cushing's syndrome, conventional antihypertensive therapy is mostly ineffective. Blood pressure response is satisfactory only after the restoration of normal cortisol levels, indicating the need for a specific treatment for hypertension in this disorder.

The relationship between cortisol production rate and serial serum cortisol estimation in patients on medical therapy for Cushing's syndrome

OBJECTIVE

The aim was to determine the target range into which mean daily serum cortisol should be lowered in patients on medical therapy for Cushing's syndrome, using isotopically estimated cortisol production rates as 'gold standard'.

DESIGN

Patients with Cushing's syndrome on medical treatment were given 12 ng of tritiated cortisol intravenously and a 24-hour urine collection was made in a single day. On the same day, serum cortisol was measured at 0900, 1200, 1500, 1800, 2100, and at 2400 h in in-patients. In addition, serum cortisol was measured at the same times as above in a group of healthy volunteers.

SUBJECTS

Twenty-two patients on medical therapy for Cushing's syndrome were studied on a total of 29 occasions. In addition, serum cortisol profiles were obtained in 12 healthy volunteers.

RESULTS

The median serum cortisol in patients with Cushing's syndrome was 400 (range 66-839) nmol/l, and in the healthy volunteers 178 (range 137-299) nmol/l. The median isotopic cortisol production rate in the patients with Cushing's syndrome was 84 mumol/24 h, range 10-343 (normal range 22-83) mumol/24 h. In the patients with Cushing's syndrome, the correlation of mean serum cortisol to cortisol production rate was +0.77 (P < 0.001). Normal rates were found when mean serum cortisol levels were between 150 and 300 nmol/l.

CONCLUSIONS

The aim of drug therapy for Cushing's syndrome should be to lower the mean serum cortisol through the day into the range 150-300 nmol/l.

[Value of ketoconazole in the treatment of Cushing disease]

Ketoconazole has been successfully used in short-term treatment of Cushing's syndrome. We treated 4 patients who had Cushing's disease with ketoconazole administered during 5 to 18 months. Two of them are still controlled after 15 months of treatment and 7 months after treatment was withdrawn. In the other two patients, treatment was ineffective primarily and after 5 months. Our data confirm the usefulness of ketoconazole in the treatment of Cushing's disease, but they also show that primary resistance and tachyphylaxis in long-term treatment may occur, as previously reported.

Inhibitors of P450-dependent steroid biosynthesis: from research to medical treatment

A number of cytochrome P450-dependent enzymes are major targets for both steroidal and nonsteroidal compounds that may be of use in the treatment of a number of androgen-independent, androgen-, estrogen- and other steroid-dependent diseases. Compounds of interest are for example aminoglutethimide and derivatives; esters of 4-pyridineacetic acid; imidazole derivatives, such as ketoconazole, liarozole, fadrozole, CGS 18320 B; bis-chlorophenyl-pyrimidine analogues; triazole derivatives vorozole and CGS 20267, and steroidal aromatase inhibitors such as 4-hydroxyandrostenedione. Some of them (e.g. ketoconazole) triggered studies to find new possibilities in medical treatment. Others are of use clinically or under clinical evaluation to provide a palliative treatment and/or cure to patients with for example prostatic carcinoma, breast cancer, hypercortisolism and benign prostatic hyperplasia.

Primaquine metabolism by human liver microsomes: effect of other antimalarial drugs

A number of drugs have been studied for their effect on the metabolism of the antimalarial drug primaquine by human liver microsomes (N = 4) in vitro. The only metabolite generated was identified as carboxyprimaquine by co-chromatography with the authentic standard. Ketoconazole, a known inhibitor of cytochrome P450 isozymes, caused marked inhibition of carboxyprimaquine formation with IC50 and K(i) values of 15 and 6.7 microM, respectively. This finding and the dependency of metabolite formation on NADPH indicates that cytochrome P450 isozyme(s) catalysed metabolite production. Of compounds actually or likely to be coadministered with primaquine to malaria patients, only mefloquine produced any inhibition (K(i) = 52.5 microM). Quinine, artemether, artesunate, halofantrine and chloroquine did not significantly inhibit metabolite formation. It seems unlikely that the concurrent administration of mefloquine, or other antimalarials, with primaquine will lead to appreciably altered disposition.

Contrasting effects of fluconazole and ketoconazole on phenytoin and testosterone disposition in man

Nine healthy male subjects received oral fluconazole 400 mg daily, ketoconazole 200 mg twice daily or no treatment for 6 days according to a randomized, cross-over design. A single 250 mg oral dose of phenytoin suspension was administered on day 5 and serum phenytoin concentrations were measured over the following 48 h. Serum testosterone concentrations were measured for 10 h after each dose of phenytoin. Ketoconazole had no significant effect on phenytoin concentrations while the mean AUC(0,48) for phenytoin was significantly higher with fluconazole (195.2 +/- 47.8 micrograms ml-1 h) than control (146.3 +/- 49.6 micrograms ml-1 h). At 48 h, the serum phenytoin concentration averaged 1.72 micrograms ml-1 under control conditions and 3.99 micrograms ml-1 with fluconazole (132% increase). AUC(0,10) for testosterone was 42% lower than control after ketoconazole administration (P less than 0.05) but increased by 33% from 55.6 +/- 9.4 ng ml-1 h (control) to 73.8 +/- 12.6 ng ml-1 h with fluconazole. AUC(0,10) values for the testosterone precursors androstenedione and 17 alpha-hydroxyprogesterone were significantly higher in the fluconazole treatment phase as were concentrations of luteinizing hormone. The mechanism and clinical significance of the increase in testosterone concentration caused by fluconazole remains to be determined.

Mefloquine metabolism by human liver microsomes. Effect of other antimalarial drugs

A number of drugs have been studied for their effect on the metabolism of the antimalarial drug mefloquine by human liver microsomes (N = 6) in vitro. The only metabolite generated was identified as carboxymefloquine by co-chromatography with the authentic standard. Ketoconazole caused marked inhibition of carboxymefloquine formation with IC50 and Ki values of 7.5 and 11.2 microM, respectively. The inhibition of ketoconazole, a known inhibitor of cytochrome P450 isozymes, and the dependency of metabolite formation on the presence of NADPH indicated that cytochrome P450 isozyme(s) catalysed metabolite production. Of compounds actually or likely to be coadministered with mefloquine to malaria patients only primaquine and quinine produced marked inhibition (IC50, 17.5 and 122 microM; Ki, 8.6 and 28.5 microM, respectively). However, despite these in vitro data with primaquine, clinical studies have failed to show any significant effect of single dose primaquine on the pharmacokinetics of mefloquine. With quinine, because peak plasma concentrations are very close to the Ki value, there is likely to be inhibition of mefloquine metabolism in patients receiving both drugs. Sulfadoxine, artemether, artesunate and tetracycline did not significantly inhibit carboxymefloquine formation.

Monitoring for adverse effects from systemic drugs used in dermatology

Systemic drugs with an associated element of risk are essential in managing many important dermatoses. This review identifies eight major drugs or drug groups used in dermatology that require systematic monitoring for adverse effects. The complete monitoring process is emphasized, including significant patient involvement in reporting key signs or symptoms that allow early diagnosis of many of these adverse effects. The concepts of "risk-risk" assessment and "critical toxicities" are defined, emphasizing their important role in maximizing drug benefits and safety. Drug-related risk factors, disease-specific risk factors, and patient characteristics or habits that increase the risks from systemic drugs are identified. Basic principles of monitoring for adverse effects, specific clinical features of the most important adverse effects, along with detailed monitoring guidelines for methotrexate, retinoids, dapsone, corticosteroids, and cyclosporine are presented.

Endocrine therapy for advanced breast cancer: a review

More than 45,000 women will die of metastatic breast cancer in the United States in 1991. Endocrine therapy remains a major option for treatment of such patients, and results in complete plus partial response rates of 30% with a median duration of approximately one year. Postmenopausal status, increased age, a prolonged disease-free interval, bone and soft tissue metastases, and positive estrogen and progesterone receptors are all associated with an increased response to endocrine therapy. The use of additive hormonal therapy, specifically antiestrogens, progestins, and aromatase inhibitors, have replaced surgical ablative procedures in the majority of patients; response rates to antiestrogen therapy, progestin therapy, and aromatase inhibitors are similar, but antiestrogens have generally been associated with the most favorable therapeutic index. At present, there is no convincing evidence that either combinations of endocrine therapies or endocrine therapy combined with chemotherapy are associated with an improvement in survival for patients with metastatic disease. Future research efforts directed at defining the molecular mechanisms of endocrine activity should facilitate clinical trials of newer and potentially more effective agents. All patients with metastatic breast cancer should be considered for at least one trial of endocrine therapy provided their metastatic disease is not rapidly progressive or life-threatening.

Management of oral health in persons with HIV infection

Prevention and treatment of oral disease is required to maintain quality of life and to improve prognosis of patients infected with the human immunodeficiency virus (HIV). Management requires a team approach, and close collaboration with the appropriate responsible physicians and other health care workers is necessary. Oral infection is frequent and usually opportunistic, and management is based on certain principles. Infections may disseminate and can be persistent and severe; multiple concurrent or consecutive infections with different microorganisms are frequent; fungal, viral, and parasitic infections are rarely curable; and long-term antimicrobial therapy may be required. This article reviews the management of oral candidiasis, hairy leukoplakia, and infections with herpes simplex virus, varicella-zoster virus, and cytomegalovirus. The management of Kaposi's sarcoma, lymphomas, aphthous ulceration, gangrenous stomatitis, bleeding, xerostomia, and adverse drug reactions is also described. Treatment should avoid further immunosuppression and inducement of xerostomia or caries, and should be designed to avoid adverse drug reactions and possible drug interactions.

Azoles, allylamines and drug metabolism

Four antifungal drugs, the azoles ketoconazole, itraconazole and fluconazole, and the allylamine terbinafine, were studied for their effects on the metabolism of cyclosporin A (CyA) and cortisol by human liver microsomes in vitro (n = 3). Ketoconazole produced marked inhibition of CyA hydroxylase (to metabolites M17 and M1) with IC50 and Ki values of 0.24 +/- 0.01 and 0.022 +/- 0.004 microM, respectively. On the basis of the IC50, itraconazole was 10 times less potent (IC50 of 2.2 +/- 0.2 microM), and fluconazole and terbinafine were each above 100 microM. No kinetic parameters were calculated for terbinafine because of the lack of inhibitory effects. Ketoconazole was the most potent inhibitor of cortisol metabolism (to 6 beta-hydroxycortisol, IC50 = 0.6 microM). Itraconazole produced marked inhibition of cortisol metabolism (IC50 = 2.4 microM), but fluconazole and terbinafine had little effect. These data confirm that ketoconazole is a potent inhibitor of cytochrome P-450-IIIA4, and this has clinical relevance. Although the inhibition with fluconazole was much less than with itraconazole at equimolar concentrations, it should be noted that in-vivo plasma concentrations of fluconazole are much greater than that of itraconazole. Clinical interactions of CyA with both fluconazole and itraconazole have been reported; in contrast to these azoles, terbinafine does not have the same interaction potential.

Keratitis, ichthyosis, and deafness (KID) syndrome: management with chronic oral ketoconazole therapy

Extensive cutaneous mycoses have been described in patients with the keratitis, ichthyosis, and deafness (KID) syndrome. We present a case occurring in a 48-year-old woman where improvement in the ichthyosiform dermatosis, stabilization of her ocular disease, and apparent partial prevention of further cutaneous malignancies occurred in association with ketoconazole therapy.

Ketoconazole treatment in Cushing's syndrome: experience in 34 patients

OBJECTIVE

Ketoconazole treatment of Cushing's syndrome has been reported in single cases and a few small groups of 5-8 patients. We report our experience in 34 patients.

DESIGN

Clinical study, with pretreatment and post-treatment evaluations.

PATIENTS

Out of 67 patients with Cushing's syndrome admitted during the last 6 years, 34 (28 females/six males; age range 14-67 years) received ketoconazole as a palliative treatment due to severe clinical conditions or management of the disease while awaiting results of definitive therapy.

MEASUREMENTS

Urinary cortisol, plasma cortisol and ACTH, and routine chemistry were measured every week for 4 weeks, and then once a month.

RESULTS

Comparing the last values (mean +/- SEM) during treatment with baseline, urinary cortisol decreased from 1296 +/- 176 to 270 +/- 69 nmol/d (n = 34; P less than 0.001); plasma cortisol decreased from 672 +/- 31 to 549 +/- 35 nmol/l (n = 34; P less than 0.001). For patients with pituitary-dependent Cushing's syndrome, urinary cortisol decreased from 1073 +/- 126 to 200 +/- 21 nmol/d (n = 28; P less than 0.001) while plasma ACTH changed from 12.5 +/- 1.3 to 11.3 +/- 0.8 pmol/l (n = 26; not significant). Twelve patients were treated for more than 6 months, and those with pituitary-dependent disease all received pituitary radiation therapy, except the two who eventually escaped pharmacological control. One additional patient with adrenal carcinoma and one with ectopic ACTH syndrome showed lack of control of urinary cortisol levels. Ketoconazole was withdrawn within the first week in two patients for allergic reaction and acute liver toxicity. Other side-effects included: asymptomatic liver function abnormalities in three patients; gastrointestinal symptoms in four; worsening of gynaecomastia in one. Rapid clinical improvement was observed together with the normalization of urinary cortisol levels, with regression of symptoms such as diabetes mellitus, hypertension, hypokalaemia, and restoration of well being.

CONCLUSIONS

These data confirm that ketoconazole is valuable in the management of hypercortisolism, provided that patients are closely watched to exclude those who may develop liver toxicity and to prevent the occurrence of adrenal insufficiency.

Activation of osmolyte efflux from cultured renal papillary epithelial cells

The rabbit renal papillary epithelial cell line PAP-HT25 accumulates sorbitol and other organic osmolytes when cultured in hypertonic media. When returned to isotonic media, PAP-HT25 cells swell because of water influx and then shrink to their normal volume because of rapid osmolyte and water efflux (volume regulatory decrease, VRD). Sorbitol efflux from PAP-HT25 cells during VRD was reduced to 18% of control by incubation of the cells with 100 microM eicosatetraynoic acid (ETYA), indicating that an enzyme that metabolizes arachidonic acid (AA) is a key component of the efflux process. Sorbitol efflux was unaffected by incubation with cyclooxygenase and lipoxygenase inhibitors but was reduced to 9% by incubation with 100 microM ketoconazole and to 37% by incubation with 100 microM SKF-525A, indicating that the cytochrome P-450 limb of the AA cascade is involved in the efflux process. The efflux of other organic osmolytes betaine and myoinositol, but not glycerolphosphorylcholine, was also inhibited by incubation with ETYA and ketoconazole.

Treatment of major depression with steroid suppressive drugs

The hypercorticism frequently observed in major depression, unaccompanied by signs of Cushing's syndrome, is still poorly understood. One suicidal young woman, with very high cortisol levels and unusual resistance to dexamethasone suppression, is described. She was successfully treated with steroid suppressive drugs (aminoglutethimide, metyrapone), had a prompt and complete remission and has remained well for more than two years on no medication. This success prompted an on-going clinical trial of this therapy. The available drugs and a working hypothesis of their action are discussed.

Steroids and depression

Patients with endogenous depression (major affective disorder) frequently have high cortisol levels, but the diurnal rhythm is usually maintained and they do not develop the physical signs of Cushing's syndrome. On the other hand, depression is a frequent feature of Cushing's syndrome regardless of etiology, and it is often relieved when the cortisol levels are reduced, by whatever means. The mechanisms of the hypercortisolemia and resistance to dexamethasone suppression commonly found in endogenous depression are poorly understood; contrary to expectations, ACTH levels are not clearly elevated. There is a striking difference in the psychiatric features seen in endogenous hypercorticism compared to those seen after exogenous administration of glucocorticoids or ACTH. This suggests that either there are other stimulating or modifying factors besides ACTH or that the steroids stimulated by ACTH or other peptides differ from those in control subjects, i.e. there may be an alteration in the metabolism of steroids in depression. Little is known about the metabolic changes or the many steroids besides glucocorticoids produced by the hyperactive steroid-producing tissue. Preliminary studies suggest that major depression may be improved by steroid suppression. It is hypothesized that steroids themselves may be important in causing and perpetuating depression.

Prostate cancer

Prostate cancer is the most common malignancy in men and the second leading cause of cancer deaths. Although the mortality rate for prostate cancer has remained unchanged for 50 years, new advances have changed classic concepts in the diagnosis and management of patients with this disease. Our understanding of the anatomy and natural history of patients with prostate cancer has been enhanced. The ability to diagnose early stage prostate tumors has been improved by the introduction of prostate-specific antigen and transrectal ultrasound. Clinical staging of patients with prostate cancer has been refined, which has decreased adverse effects of inappropriate treatment. Modifications in the technique of radical prostatectomy have minimized the morbidity associated with this procedure, making it a more attractive therapeutic option. DNA ploidy analysis holds promise as a predictor of response to hormonal therapy. New agents are available to reduce adverse effects of hormonal therapy. In addition, traditional ideas about the timing of hormonal therapy and the use of total androgen blockade are being challenged. These changes may presage an improved quality of life and improve survival for patients with prostate cancer.

High-dose itraconazole in the treatment of severe mycoses

Eight patients with systemic mycoses and with prior treatment failures were treated with itraconazole (600 mg/day) for a mean duration of 5.5 months. All six patients without AIDS experienced improvement or stabilization of their fungal infections while receiving high-dose itraconazole, although two patients later experienced treatment failures, one by relapse and one by progression, on lower doses. Treatment failures also occurred in the two patients with AIDS and cryptococcal meningitis. The failures were associated with low serum itraconazole concentrations (less than 2.5 micrograms/ml) in both patients. All other patients had mean trough levels in serum above 5 micrograms/ml. One patient who was improving on 600 mg/day developed a progressive infection after reduction of the dose to 400 mg/day. Side effects included reversible adrenal insufficiency in one patient; severe hypokalemia, mild diastolic hypertension, and rhabdomyolysis in one patient; mild hypokalemia and hypertension in four other patients; and breast tenderness in one patient. The mean decrease in serum potassium during treatment was statistically significant (P = 0.05). Selected patients with severe systemic mycoses may benefit from prolonged high-dose itraconazole treatment. However, 600 mg/day may be approaching the upper limits of acceptable dosing for long-term treatment.