Neurotoxicity of interferon-alpha

Interferon-β suppresses inflammatory pain through activating µ-opioid receptor

Interferons (IFNs) are cytokines secreted by infected cells that can interfere with viral replication. Besides activating antiviral defenses, type I IFNs also exhibit diverse biological functions. IFN-β has been shown to have a protective effect against neurotoxic and inflammatory insults on neurons. Therefore, we aimed to investigate the possible role of IFN-β in reducing mechanical allodynia caused by Complete Freund's Adjuvant (CFA) injection in rats. We assessed the antinociceptive effect of intrathecal IFN-β in naïve rats and the rats with CFA-induced inflammatory pain. After the behavioral test, the spinal cords of the rats were harvested for western blot and immunohistochemical double staining. We found that intrathecal administration of IFN-β in naïve rats can significantly increase the paw withdrawal threshold and paw withdrawal latency. Further, the intrathecal injection of a neutralizing IFN-β antibody can reduce the paw withdrawal threshold and paw withdrawal latency, suggesting that IFN-β is produced in the spinal cord in normal conditions and serves as a tonic inhibitor of pain. In addition, intrathecal injection of IFN-β at dosages from 1000 U to 10000 U demonstrates a significant transient dose-dependent inhibition of CFA-induced inflammatory pain. This analgesic effect is reversed by intrathecal naloxone, suggesting that IFN-β produces an analgesic effect through central opioid receptor-mediated signaling. Increased expression of phospho-µ-opioid receptors after IFN-β injection was observed on western blot, and immunohistochemical staining showed that µ-opioids co-localized with IFN-α/βR in the dorsal horn of the spinal cord. The findings of this study demonstrate that the analgesic effect of IFN-β is through µ-opioid receptors activation in spial cord.

[Central nervous system complications in patients undergoing cytotoxic chemotherapy and targeted therapies]

Anti-cancer treatments (cytotoxic chemotherapies, targeted therapies and hormonotherapies) are known to induce early and delayed neurological toxicities. Acute encephalopathies and posterior reversible encephalopathies are better known and described, physiopathological hypotheses are emerging. It is difficult to discriminate what drug is causing the symptoms in patients treated with multiple cytotoxic drugs. Methotrexate and ifosfamide are responsible for acute encephalopathies. L-asparaginase and methotrexate or targeted therapies may induce cerebrovascular complications. As life expectancy increases and more complex regimen including innovative targeted therapies are developed, new toxicity profiles can be expected. To be able to provide an early diagnosis, prevention, and treatment (when existing) of these pathologies remains a tremendous challenge that would allow a good quality of life with social and professional life after their cancer is cured.

Successful treatment of kaposiform hemangioendothelioma and tufted angioma with vincristine

BACKGROUND

Kaposiform hemangioendothelioma (KHE) and tufted angioma (TA) are rare, locally aggressive vascular tumors. Although currently classified as separate entities, they are becoming increasingly recognized as a spectrum of the same pathology. There is a well-recognized association with Kasabach-Merritt phenomenon KHE and TA are considered neoplasms of intermediate malignancy because of infiltrative growth, local aggressiveness, and variable prognosis. To date, definitive treatment for these vascular tumors has had limited success.

AIM

To evaluate the safety, efficacy, and role of vincristine in the treatment of KHE and TA.

METHODS

Case review of patient files and pathology reports at The Children's Hospital at Westmead from 1995 to 2009.

RESULTS

Twelve cases with KHE or TA were identified. Seven cases were treated with vincristine. The survival rate in the vincristine group was 100%. Mean age of diagnosis was 30 months (range birth to 9 y). 6 patients were female (85.7%). Mean time of the follow-up was 4 years (range 4 mo to 8 y). Out of the 7 cases treated with vincristine, 3 patients had associated Kasabach-Merritt phenomenon (43%). Complete resolution, regression in size, and improvement in analgesia were found in 1 case (14%), 3 cases (43%) and 2 cases (29%), respectively. Vincristine related side effects occurred in 2 cases (29%).

CONCLUSIONS

Vincristine is an effective treatment option for KHE/TA. It is associated with a low side effect profile and should be considered as the first-line agent.

Treatment of endocrine pancreatic tumors

Endocrine pancreatic tumors are rare with an incidence of 4 per million inhabitants. Most tumors are malignant except for insulinomas that usually are benign. They are slowly growing in the majority of cases but there are exceptions with rapidly progressing malignant carcinomas. Because of the rarity of these tumors large randomized trials are difficult to accomplish. However, most physicians treating these patients agree that surgery should be considered in all cases and that medical treatment with chemotherapy and biotherapy is well established for this group of patients.

Chemotherapy induced reversible posterior leukoencephalopathy syndrome

The reversible posterior leukoencephalopathy syndrome (RPLES) is a condition characterised by reversible neurological and radiological findings that has been associated with use of immunosuppressive, chemotherapeutic and more recently novel targeted therapies. We describe the case of a 50-year-old woman with advanced non-small cell lung cancer who developed status epilepticus shortly after receiving cisplatin and gemcitabine chemotherapy. The clinical, radiological and EEG findings during and post event are presented and are in keeping with a diagnosis of RPLES. Early recognition of this rare syndrome, supportive management and withdrawal of the offending agent appear to result in a reversal of the manifestations described.

Upward transtentorial herniation, hydrocephalus, and cerebellar edema in hypertensive encephalopathy

BACKGROUND

Edema of the cerebellum with secondary obstructive hydrocephalus is a rare presentation of hypertensive encephalopathy. The authors report an unusual case of isolated posterior fossa swelling with upward transtentorial herniation and hydrocephalus causing neurologic deterioration. These patients are often initially evaluated by a neurologist because of the acute neurologic symptoms. Prompt diagnosis with aggressive blood pressure control may obviate the need for emergent cerebrospinal fluid (CSF) diversion.

REVIEW SUMMARY

This is a case report of a 26-year-old man who presented to the emergency room with confusion and somnolence over a 2-day period. His initial blood pressure was 175/110 mmHg. On examination he was disoriented, with a Glasgow Coma Scale score of 12 points, opening his eyes only to loud verbal stimuli, verbalizing inappropriately, and he was only able to follow simple commands. Neuroimaging revealed edema of the cerebellar folia with noncommunicating hydrocephalus and upward transtentorial herniation. Differential diagnoses of posterior fossa tumor, rhombencephalitis, and hypertensive encephalopathy were entertained. A thorough literature review is included with the discussion of this case. The patient underwent emergent ventriculostomy for CSF drainage and prompt blood pressure control with nitroprusside. After 48 hours of CSF drainage and correction of his hypertension, his neurologic examination normalized. Repeat imaging revealed near resolution of the obstructive hydrocephalus and cerebellar edema.

CONCLUSION

Isolated edema of the cerebellum with upward transtentorial herniation and obstructive hydrocephalus is a rare presentation of hypertensive encephalopathy and should be considered in patients with an acute hypertensive crisis and mental status changes. This entity responds to prompt blood pressure control; however, emergent ventriculostomy by a neurosurgical team should be entertained for neurologic deterioration secondary to significant obstructive hydrocephalus, as illustrated in this case.

Interferon-induced depression: prevalence and management

BACKGROUND

Interferon-induced depression ranges from 0 to 50%. Interferon schedule and a history of psychiatric illnesses are not enough to predict who will develop symptoms and who will not.

AIMS

To assess the prevalence of depression during interferon therapy; to test whether Minnesota Multiphasic Personality Inventory is useful in clinical practice for the early identification of patients at risk of depression; whether and how the depression can be cured.

PATIENTS

One hundred and eighty-five patients treated with interferon and ribavirin for chronic hepatitis C.

METHODS

Before therapy, all patients underwent a Minnesota Multiphasic Personality Inventory and a clinical examination, specifically for the identification of depressive symptoms.

RESULTS

Thirty-one patients developed a psychiatric disorder, 11 of them requiring treatment with anti-depressant drugs. Among the 18 patients with Minnesota Multiphasic Personality Inventory positive tests, 16 developed a psychiatric disorder, 8 of them a severe disorder (sensitivity of 0.58; 0.73 for severe disorders). Among the 154 who did not develop psychiatric side effects, 152 had a negative Minnesota Multiphasic Personality Inventory (specificity: 0.99). Severe psychiatric disorders were successfully treated with anti-depressant drugs.

CONCLUSIONS

Psychiatric side effects are easy to see during interferon therapy. A psychiatric evaluation should be considered on all patients before treatment. If depression develops, it should be treated aggressively, and selective serotonin re-uptake inhibitors are the anti-depressants of choice.

Plasma levels of citalopram in depressed patients with hepatitis C

Hepatitis C affects an estimated 4 million Americans and 100 million people worldwide. Rates of depression are higher than that seen in the general population. Antidepressant therapy is often initiated at lower doses in patients with liver disease because of concerns about impaired metabolism and clearance. This study assessed plasma levels of citalopram in 15 subjects with hepatitis C and major depression during an 8-week trial. The mean citalopram dose at study completion was 26.67 mg/day. Mean plasma levels of citalopram, compared with levels previously reported, were lower than expected (at 10 mg/day [N = 1]: 21 ng/ml [N = 1]; at 20 mg/day [N = 8]: mean = 42.25 ng/ml, SD = 18.38; at 30 mg/day [N = 1]: 54 ng/ml; at 40 mg/day [N = 5]: mean = 76.2 ng/ml, SD = 35.86). There was a tendency for lower plasma levels to be found in those subjects receiving interferon, although a statistically significant difference was not observed. Citalopram was well tolerated. The results of this study suggest that patients with major depression and hepatitis C, but without evidence of severe liver disease, may be able to tolerate usual recommended doses of citalopram, thus avoiding the potential for undertreatment of the depression.

Atypical propriospinal myoclonus with possible relationship to ? interferon therapy

We report on a man who received interferon-alpha 2a therapy for kidney cancer and who subsequently developed propriospinal myoclonus. The myoclonus was noted at rest and during movement. The jerks were reinforced by cutaneous stimuli and tendon taps and spread to the spinal cord via polysynaptic propriospinal pathways. Cerebrospinal fluid analysis, spinal cord magnetic resonance imaging, electroencephalogram with back-averaging, and somatosensory-evoked potentials were normal. No antineuronal antibodies were found. Although the mechanism of interferon neurotoxicity remains unclear, the possible responsibility of interferon was considered, as no focal lesion or paraneoplastic pathology were disclosed.

Posterior reversibile encephalopathic syndrom: case report and review of literature

INTRODUCTION Reversible Posterior Leukoencephalopathy Syndrome was introduced into clinical practice in 1996 in order to describe unique syndrome, clinically expressed during hypertensive and uremic encephalopathy, eclampsia and during immunosuppressive therapy [1 ]. First clinical investigations showed that leucoencephalopathy is major characteristic of the syndrome, but further investigations showed no significant destruction in white cerebral tissue [2, 3,4]. In majority of cases changes are localize in posterior irrigation area of the brain and in the most severe cases anterior region is also involved. Taking into consideration all above mentioned facts, the suggested term was Posterior Reversible Encephalopathy Syndrome (PRES) for the syndrome clinically expressed by neurological manifestations derived from cortical and subcortical changes localized in posterior regions of cerebral hemispheres cerebral trunk and cerebellum [5]. CASE REPORT Patient, aged 53 years, was re-hospitalized in Cardiovascular Institute "Dedinje" two months after succesfull aorto-coronary bypass performed in June 2001 due to the chest bone infection. During the treatment of the infection (according to the antibiogram) in September 2001, patient in evening hours developed headache and blurred vision. The recorded blood pressure was 210/120 mmHg so antihypertensive treatment was applied (Nifedipin and Furosemid). After this therapy there was no improvement and intensive headache with fatigue and loss of vision developed. Neurological examination revealed cortical blindness and left hemiparesis. Manitol (20%, 60 ccm every 3 hours) and iv. Nytroglicerin (high blood pressure). Brain CT revealed oedema of parieto-occipital regions of both hemispheres, more emphasized on the right. (Figure 1 a, b, c). There was no sign of focal ischemia even in deeper sections (Figure 1d, e, f). Following three days enormous high blood pressure values were registered. On the fourth day the significant clinical improvement occurred with lowering of blood pressure, better mental state and better vision. There was no sign of left hemiparesis on the 7th day. On the 9th day there were no symptoms or sign of disease. Control brain CT (15th day) was normal. ETHIOPATHOGENESIS Most common causes of PRES are hypertensive encephalopathy [6-8], pre-eclampsia/eclampsia [9-12] cyklosporin A administration [13-22] and uremic encephalopathy [23]. There are several theories about the mechanism for PRES in hypertensive encephalopathy (reversible vasospasm and hyperperfusion) and administration of cyclosporin A (neurotoxic effect). CLINICAL PICTURE Most common symptoms are headache, nausea, vomiting, confusion, behavioural changes, changes of conciousnes (from somnolencia to stupor), vision disturbances (blurred vision, haemianopsia, cortical blindness) and epileptic manifestations (mostly focal attacs with secondary generalization). Mental functions are characterised with decreased activity and reactivity, confusion, loss of concentration and mild type of amnesia. Lethargy is often initial sign, sometimes accompanied with phases of agitation. Stupor and coma rarely occurred. DIAGNOSIS In patients with hypertensive ecephalopathy and eclampsia high blood pressure is registered. Neurological examination revealed vision changes and damages of mental function as well as increased reflex activity. Today, brain MRI and CT are considered the most important diagnostic method for the diagnosis and follow-up of patients with PRES [6]. Brain MRI better detects smaller focal parenhim abnormalities than brain CT.The most often neuroradiological finding is relatively symetrical oedema of white cerebral tissue in parieto-occipital regions of both cerebral hemispheres. Gray cerebral tissue is sometimes involved, usually in mild form of disease. Diagnosis of this "cortical" form of PRES is possible by MR FLAIR (Fluid-Attenuated Inversion Recovery) technique [5]. TREATMENT Therapeutic strategy depends on the cause of PRES and clinical picture. Most important are blood pressure regulation (labetalol, nitroprusid, diuretici), control of epileptic attacs (phenytoin), anti-oedema therapy. (Manitol), induction of vaginal delivery in eclampsia and discontinuation of cyclosporin therapy. In most cases there are no neurological manifestations after the 7th day but some studies showed normalization of clinical finding after one year and more.

Incidence and clinical course of major depression in patients with chronic hepatitis type C undergoing interferon-alpha therapy: a prospective study

This study examined the incidence, clinical course and its risk factors for major depression in patients with chronic hepatitis type C undergoing interferon-alpha therapy. Ninety-nine subjects underwent the psychiatric interviews for diagnosis of major depressive episode according to the DSM-IV criteria before the start of interferon therapy, and once every 4 weeks during both the 24-week treatment period and 12 weeks after the end of therapy. Depressive symptoms were also evaluated using the Hamilton Rating Scale for Depression. Major depression occurred during interferon therapy in 23 patients (23.2%). In 73.9% of them depression occurred within 8 weeks after the start of therapy. Twenty-two patients with depression completed the therapy and 59.1% of them achieved remission by the end of therapy with a mean duration of 11.6 weeks. Although the other 40.9% were not in remission at the end of therapy, they achieved remission within 12 weeks thereafter. The only risk factor for depression was advanced age. Depression occurs frequently among patients with hepatitis type C undergoing interferon-alpha therapy. Such patients require careful observation, and psychiatrists should be sufficiently aware of this significant psychiatric complication of interferon therapy.

The benefit of long-term interferon alfa therapy for symptomatic mixed cryoglobulinemia (cutaneous vasculitis/membranoproliferative glomerulonephritis) associated with chronic hepatitis C infection

The efficacy of long-term interferon therapy for chronic hepatitis C infection with symptomatic mixed cryoglobulinemia has not clearly been defined. We describe a patient with chronic hepatitis C, symptomatic mixed cryoglobulinemia (cutaneous vasculitis), and membranoproliferative glomerulonephritis (MPGN) who responded clinically, biochemically, and virologically to a 1-year course of interferon therapy. Interferon side effects were minimal. Relapse occurred when interferon was discontinued, and suppressive maintenance interferon therapy was required for clinical, biochemical, and virologic remission. During the 5th year of maintenance therapy, she developed potential side effects that necessitated discontinuation of interferon treatment. After treatment stoppage, a clinical, biochemical, and virologic remission was maintained for more than 1 year. However, the potential side effects, which included eye irritation, arthralgias, myalgias, fatigue, insomnia, memory loss, and depression, persisted. Ophthalmologic, rheumatologic, and neurologic evaluations were nondiagnostic. Psychometric testing revealed dementia and mood disorder. Because the disabling symptoms persisted after 9 months, a health-related quality of life assessment was carried out with the SF-36 survey. Compared with healthy individuals and patients with chronic hepatitis C, our case had a lower health-related quality of life assessment on six out of seven scales and on four out of seven scales of the SF-36 survey, respectively. This case report indicates that long-term maintenance interferon therapy was effective in the treatment of symptomatic mixed cryoglobulinemia and its renal complications and resulted in a clinical, biochemical, and virologic sustained response. It is postulated that the side effects of long-term interferon therapy in this setting may be problematic.

Cytokines and advanced cancer

Cytokines have a major role in promoting the growth and spread of cancers. Elevated levels of several cytokines have been described in cancer patients. Evidence from animal and human studies suggests that cytokines may contribute to a wide range of symptoms in advanced cancer, including: asthenia, pain, drowsiness, cognitive failure, agitated delirium, autonomic dysfunction, anorexia, cachexia, fever and metabolic abnormalities. Considerable effort is being directed at finding anticytokine treatments, raising the possibility of new options for symptoms that are currently difficult to control.

Psychiatric side effects of interferon therapy: prevalence, proposed mechanisms, and future directions

The increasing use of interferon (IFN) in treating a variety of disorders including, malignant melanoma and hepatitis C, has resulted in the identification and increasing concern about the psychiatric side effects that can result from treatment. These effects can occur either shortly after beginning IFN therapy or later as a result of continued treatment. Studies have reported the incidence of later side effects, which include symptoms of depression, anxiety, and occasional suicidal ideation, to be from 0% to 70%. Case studies have demonstrated that pharmacologic interventions are beneficial in reducing iatrogenic psychiatric symptoms while allowing patients to maintain IFN therapy. The present article provides an overview of the psychiatric effects of IFN therapy, the proposed mechanisms of these side effects, and case studies that provide mechanistic support. In addition, limitations of the current literature are provided with suggestions for treating physicians and a discussion of possible future research directions.

Adverse effects and other safety aspects of the hepatitis C antivirals

The preferred treatment for patients with chronic hepatitis C, either treatment-naive, relapsers or nonresponders to IFN monotherapy, is now IFN-ribavirin combination treatment. The adverse effects of IFN are well established and familiar to hepatologists all over the world. More than 25,000 patients worldwide have been treated with combination therapy. Patients re-treated with a combination regimen are more likely to tolerate IFN better than treatment-naive patients, probably due to better case selection. The safety profile of regimens containing IFN-alpha plus ribavirin is generally consistent with the safety profile of each agent when employed in monotherapy; there is little or no synergistic toxicity. Anorexia, dyspnoea, cough, pruritus and rash are the only adverse events reported at a consistently higher frequency with combination treatment, and are usually mild to moderate in severity and rarely result in dose reductions or discontinuation. The primary cause of dose reduction for combination therapy is haemolytic anaemia, which can be managed effectively. The most common reason for discontinuation of therapy for either type of therapy is psychiatric problems, especially depression, which seems to be closely related to the duration of treatment. In patients receiving combination therapy, anaemia and depression need close monitoring, and dose modification in some cases. Strict guidelines for dose reduction and discontinuation are essential to prevent serious adverse events. Because of the teratogenic risk from ribavirin, pregnancy is contraindicated in patients or their partners during and 6 months after treatment.

Hypertensive encephalopathy: complication in children treated for myeloproliferative disorders--report of three cases

We routinely perform echo-planar diffusion-weighted sequences in all brain magnetic resonance (MR) imaging studies. When three children undergoing chemotherapy for acute leukemia presented with seizures, conventional MR images demonstrated what appeared to be acute, posterior, parasagittal infarcts. However, diffusion-weighted images were normal. These MR imaging findings were consistent with those of hypertensive encephalopathy. Early recognition and treatment of minimal hypertension in these patients allows reversal of encephalopathy.

[Effectiveness and dangers of interferon-alpha in the treatment of severe hemangiomas in infants]

Alarming hemangiomas, due to their site or repercussions, require pharmacological treatment. Corticosteroid therapy is indicated by first intention. In the event of failure, interferon alpha is proposed.

CASE REPORTS

Case 1. A five-week-old infant was admitted to hospital for an extensive hemangioma of the left side of the face and neck with necrosis of the upper lip and ear. Prednisolone (2 mg/kg/day) by intravenous route brought about no improvement. Interferon alpha 2a (3 MU/m2/day of Referon by subcutaneous injection) enabled regression of lesions from the sixth month of treatment. After 11 months of treatment, the hemangioma had all but disappeared and interferon therapy was stopped. Repair surgery was planned at 24 months of age. Case 2. A one-month-old infant suffered from a hemangioma of the right side of the face with orbital invasion and risk of amblyopia. Prednisone (2 mg/kg/day) by oral route was ineffective. Interferon alpha 2a enabled regression of the hemangioma and the eye opened from the third month of treatment. Interferon therapy was stopped after 14 months. Initial repair surgery intervention was possible at two years of age. Spastic paraplegia was diagnosed at 18 months of age. The brain and medullar magnetic resonance imaging was normal. No etiology could explain the neurological attack. The possible toxic effect of interferon alpha is discussed.

CONCLUSION

Interferon alpha is an effective treatment for hemangiomas. It significantly reduces spontaneous regression time. The uncertainty of long-term effects in infants with hemangiomas incites its indication to be limited to alarming corticosteroid-resistant forms and necessitates prolonged neurological surveillance.

A case of seizures 1 week after the cessation of interferon-alpha therapy

We report on a 60-year-old woman with a history of bipolar mood disorder who had seizures and developed a delirious state 1 week after the cessation of interferon-alpha (IFN-alpha) for chronic hepatitis C. The IFN-alpha was administered to the patient for 7 weeks (266 million IU). One week after the cessation of IFN-alpha therapy, the patient had four generalized tonic-clonic seizures over a 2-day period and developed a delirious state for 2 months. We consider these seizures and delirious state to be related to IFN-alpha.

Effect of interferon-alpha treatment of chronic hepatitis C on health-related quality of life

Studies of interferon-alpha (IFN-alpha) therapy for chronic hepatitis C have focused on viral clearance; however, few have evaluated patient's health-related quality of life during therapy. This study evaluates health-related quality of life and the prevalence of anxiety and depression in patients with chronic hepatitis C before, during, and following IFN-alpha therapy. Patients undergoing IFN-alpha therapy for chronic hepatitis C were asked to complete health status measures as well as anxiety and depression inventories before, during, and following IFN-alpha therapy. These measures were compared to the results of healthy adults in the general US population. Thirty-eight of forty-eight eligible patients (79%) with chronic hepatitis C completed the questionnaires. Respondents demonstrated a significant increase in depression during the sixth month of interferon therapy in comparison to pretreatment results. Anxiety scores improved significantly after one month of IFN-alpha in comparison to pretreatment results. Scores on the health status measures did not vary with IFN-alpha therapy. Patient responses were analyzed with respect to biochemical response (normalized transaminases) to IFN-alpha. IFN-alpha responders, who were aware of their transaminase results, exhibited lower scores on anxiety subscales during and after therapy (P = 0.02-0.04). Scores on the health status subscale, role emotional, improved in IFN-alpha responders compared to nonresponders during the sixth month of therapy (P = 0.02). Response to IFN-alpha therapy was not associated with any other differences on subscale analysis. Patients with chronic hepatitis C exhibited health perceptions similar to the general US population, and these were unchanged during IFN-alpha therapy. However, the incidence of depression significantly increased during the sixth month of IFN-alpha therapy. IFN-alpha responders exhibited fewer emotional problems as well as a lower incidence of anxiety during and following therapy.

Quinolinic acid production by macrophages stimulated with IFN-gamma, TNF-alpha, and IFN-alpha

Quinolinic acid (QUIN) has been associated with several inflammatory neurologic disorders, including AIDS dementia complex (ADC). Recent studies suggest that activation of macrophages with either HIV-1 or interferon-gamma (IFN-gamma) can lead to QUIN production. However, the importance of other cytokines, especially those related to the macrophage and that are especially important in ADC pathogenesis, remains unclear. We, therefore, sought to determine the role of tumor necrosis factor-alpha (TNF-alpha) and IFN-alpha in the production of QUIN. Primary human macrophages were stimulated with two different concentrations of these cytokines alone, in combination with each other, and with IFN-gamma. QUIN concentrations in the supernatants were then measured by mass spectrometry at 24, 48, and 72 hs. Results at 72 h showed significant increases in QUIN production in the cells stimulated with IFN-gamma (10297 +/- 170 nmol/L) and also in those stimulated with IFN-alpha (3600 +/- 113 nmol/L), whereas TNF-alpha-stimulated macrophages produced low levels of QUIN (1108 +/- 23 nmol/L). Macrophages stimulated with the cytokine combinations TNF-alpha and IFN-gamma, IFN-alpha, and IFN-gamma, and TNF-alpha and IFN-alpha also resulted in increases in QUIN production (11471 +/- 77.6 nmol/L, 16656 +/- 184 nmol/L, and 3369 +/- 120.5 nmol/L, respectively). The increases in QUIN production in all of the cytokine treatments approached or exceeded in vivo concentrations of QUIN that have been shown to be neurotoxic. These data further support a role for QUIN in cytokine-mediated neuronal death in inflammatory disorders of the brain, especially ADC.

Case report: interferon induced coma in Sheehan's syndrome

A 54-year-old woman who was being treated with 10 million units (mu) of natural interferon (IFN)-alpha per day for chronic active hepatitis C at a local clinic, developed coma on the fourth day of treatment. On admission to Yamagata University Hospital, she was still in a state of semicoma with severe hyponatraemia (122 mEq/L) and hypochloraemia (89 mEq/L). After the administration of electrolytes, her condition improved remarkably. Endocrinological loading tests showed a hypofunction of the anterior pituitary gland. In consideration of these results, and her past experiences of haemorrhage during childbirth and subsequent amenorrhoea, we diagnosed her illness as a coma as a result of Sheehan's syndrome which had become overt during IFN therapy. She recovered completely after treatment with hydrocortisone and l-thyroxine.

Treatment of three patients with systemic mastocytosis with interferon alpha-2b

It has been reported that the administration of interferon alpha-2b is of potential benefit in the treatment of mastocytosis based on a single patient study (NEJM, Feb 27, 1992, 326(9):619-623). Following this report, we administered interferon alpha-2b at a dose of 4 to 5 million units per square meter of body surface area for at least 12 months to one patient with mastocytosis with an associated hematologic disorder (patient 1), one patient with aggressive systemic mastocytosis (patient 2), and one patient with indolent mastocytosis (patient 3). Patients were monitored with the following clinical and laboratory parameters: serial bone marrow biopsies and aspirates, patient log of histamine release attacks, medication dependency, plasma tryptase levels, serum lactate dehydrogenase (LDH) levels, white blood cell counts and differentials, extent of urticaria pigmentosa lesions, bony involvement, and extent of gastrointestinal involvement and hepatomegaly. We also examined the ability of interferon alpha-2b to inhibit recombinant human stem cell factor (rhSCF)-dependent mast cell proliferation from CD34+ bone marrow-derived cells. All patients demonstrated continued progression of disease in one or more clinical criteria at one year of therapy. Similarly, interferon alpha-2b did not inhibit the culture of mast cells from CD34+ bone marrow-derived cells in the presence of SCF. Thus, in our study of three patients with systemic mastocytosis, treatment with interferon alpha-2b was found to be ineffective in controlling progression of disease.

Mapped auditory evoked potentials before and after interferon treatment

Neurotoxicity induced by interferon (IFN) is revealed by neurobehavioral changes, such as irritability, somnolence, lack of motivation, and delayed ideation. As these side effects persist throughout IFN-alpha treatment, we studied cerebral mapped auditory evoked potentials (MAEP) in 20 hepatitis C virus antibody (HCV Ab)-positive chronic active hepatitis patients before and after administration of leukocyte IFN-alpha (i.m. 3,000,000 IU). Some of the main components of MAEP, such as morphology, latency, and power spectra, were altered before IFN injection. These parameters changed 7 h after administration as revealed by increased quality and quantity of acoustic signal reaching the brain cortex and appearance of physiologic waves in patients with mild/intermediate liver disease. These effects revealed 48 h after IFN administration.

A reversible posterior leukoencephalopathy syndrome

BACKGROUND AND METHODS

In some patients who are hospitalized for acute illness, we have noted a reversible syndrome of headache, altered mental functioning, seizures, and loss of vision associated with findings indicating predominantly posterior leukoencephalopathy on imaging studies. To elucidate this syndrome, we searched the log books listing computed tomographic (CT) and magnetic resonance imaging (MRI) studies performed at the New England Medical Center in Boston and Hôpital Sainte Anne in Paris; we found 15 such patients who were evaluated from 1988 through 1994.

RESULTS

Of the 15 patients, 7 were receiving immunosuppressive therapy after transplantation or as treatment for aplastic anemia, 1 was receiving interferon for melanoma, 3 had eclampsia, and 4 had acute hypertensive encephalopathy associated with renal disease (2 with lupus nephritis, 1 with acute glomerulonephritis, and 1 with acetaminophen-induced hepatorenal failure). Altogether, 12 patients had abrupt increases in blood pressure, and 8 had some impairment of renal function. The clinical findings included headaches, vomiting, confusion, seizures, cortical blindness and other visual abnormalities, and motor signs. CT and MRI studies showed extensive bilateral white-matter abnormalities suggestive of edema in the posterior regions of the cerebral hemispheres, but the changes often involved other cerebral areas, the brain stem, or the cerebellum. The patients were treated with antihypertensive medications, and immunosuppressive therapy was withdrawn or the dose was reduced. In all 15 patients, the neurologic deficits resolved within two weeks.

CONCLUSIONS

Reversible, predominantly posterior leukoencephalopathy may develop in patients who have renal insufficiency or hypertension or who are immunosuppressed. The findings on neuroimaging are characteristic of subcortical edema without infarction.