Renal involvement in eosinophilic granulomatosis with polyangiitis (EGPA): a multicentric retrospective study of 63 biopsy-proven cases

OBJECTIVE

Eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic small-vessel vasculitis characterized by asthma, hypereosinophilia and ANCA positivity in 40% of patients. Renal involvement is rare and poorly described, leading to this renal biopsy-proven based study in a large EGPA cohort.

METHODS

We conducted a retrospective multicentre study including patients fulfilling the 1990 ACR criteria and/or the 2012 revised Chapel Hill Consensus Conference criteria for EGPA and/or the modified criteria of the MIRRA trial, with biopsy-proven nephropathy.

RESULTS

Sixty-three patients [27 women, median age 60 years (18-83)] were included. Renal disease was present at vasculitis diagnosis in 54 patients (86%). ANCA were positive in 53 cases (84%) with anti-MPO specificity in 44 (83%). All patients had late-onset asthma. Peripheral neuropathy was present in 29 cases (46%), alveolar haemorrhage in 10 (16%). The most common renal presentation was acute renal failure (75%). Renal biopsy revealed pauci-immune necrotizing GN in 49 cases (78%). Membranous nephropathy (10%) and membranoproliferative GN (3%) were mostly observed in ANCA-negative patients. Pure acute interstitial nephritis was found in six cases (10%); important interstitial inflammation was observed in 28 (44%). All patients received steroids with adjunctive immunosuppression in 54 cases (86%). After a median follow-up of 51 months (1-296), 58 patients (92%) were alive, nine (14%) were on chronic dialysis and two (3%) had undergone kidney transplantation.

CONCLUSION

Necrotizing pauci-immune GN is the most common renal presentation in ANCA-positive EGPA. ANCA-negative patients had frequent atypical renal presentation with other glomerulopathies such as membranous nephropathy. An important eosinophilic interstitial infiltration was observed in almost 50% of cases.

Normal intelligence in children with prenatal exposure to carbamazepine

OBJECTIVE

To investigate the effect of antiepileptic drugs, especially carbamazepine and valproate, on intelligence in prenatally exposed children of mothers with epilepsy.

METHODS

Intelligence of 182 children of mothers with epilepsy (study group) and 141 control children was tested in a blinded setting at preschool or school age using Wechsler Preschool and Primary Scale of Intelligence-Revised or Wechsler Intelligence Scale for Children-Revised. Data on maternal antiepileptic treatment and seizures during pregnancy were gathered prospectively. The study group represented approximately 50% of the children born to mothers with epilepsy in Uusimaa province during 1989 through 1994. One hundred seven children were exposed to antiepileptic monotherapy: 86 to carbamazepine and 13 to valproate. Thirty children were exposed to polytherapy: 23 combinations included carbamazepine, and 17 included valproate. The median maternal doses and blood levels during the second half of pregnancy were 600 mg and 26 micro mol/L for carbamazepine and 950 mg and 300 micro mol/L for valproate.

RESULTS

The mean verbal and nonverbal IQ scores in the children exposed in utero to carbamazepine monotherapy were 96 (95% CI, 93-100) and 103 (95% CI, 100-106). They did not differ from control subjects, whose mean verbal and nonverbal IQ scores were 95 (95% CI, 92-97) and 102 (95% CI, CI, 100-105). Significantly reduced verbal IQ scores were found in children exposed to valproate (mean, 82; 95% CI, 78-87) and to polytherapy (mean, 85; 95% CI, 80-90) compared with the other study group children and control subjects.

CONCLUSIONS

Carbamazepine monotherapy with maternal serum levels within the reference range does not impair intelligence in prenatally exposed offspring. Exposures to polytherapy and to valproate during pregnancy were associated with significantly reduced verbal intelligence. The independent effects of valproate remain unconfirmed because the results were confounded by low maternal education and polytherapy.

[Chronic lesions of the ulnar artery due to repeated occupational microtrauma complicated by acute arterial occlusion]

A case of ulnar artery occlusion following repeated micro-trauma to one hand is reported. Following resection of the diseased portion of the artery and reconstruction with an interposition vein graft. The patient recovered normal use of the hand. Pathologic examination of the artery confirmed the operative findings. This case is typical of the vascular problems of the hand associated with certain occupations.

Cortical perfusion assessment with 123I-isopropyl amphetamine (123I-IAMP) in normal pressure hydrocepha lus (NPH)

NPH can be reversible after cerebrospinal fluid (CSF) diversion. In the past no reliable criteria could be defined to predict the successful outcome of CSF shunting. Several authors demonstrated an increased cerebral blood flow after lumbar puncture in patients with NPH, indicating an underlying impairment of cerebral circulation autoregulation. 123I-AMP brain tomoscintigraphy was applied to 23 individuals with NPH before and after CSF drainage. Of these 23 patients, 10 underwent surgical shunting. The frontal and parietal hypoactive cortical pattern was present in NPH but not pathognomonic. Under stimulation of CSF pressure lowering, seven patients with improved outcome after shunting demonstrated an increase of cerebral perfusion in these areas, whereas a decrease of activity was found in three patients whose clinical status was unchanged after CSF diversion. This tomoscintigraphic test may be an interesting additional criterion for surgical admission.

Minor anomalies in offspring of epileptic mothers

In a prospective study, 121 children of mothers with epilepsy (study group) and 105 control children were examined in a blinded fashion at age 5 1/2 years for 80 minor physical anomalies, including nine typical features previously reported characteristic of fetal hydantoin syndrome. Of the study group, 106 children had been exposed to antiepileptic drugs (82 to phenytoin) during pregnancy; 44 (36%) mothers had had generalized convulsions during pregnancy. One hundred fourteen mothers and 87 fathers of study group children and 101 mothers and 58 fathers of control children were also examined. A significant excess of minor anomalies considered characteristic of hydantoin syndrome was observed in children of epileptic mothers and in epileptic mothers, compared with the control group. There was no excess of other minor anomalies studied. Several minor anomalies previously regarded as typical of fetal hydantoin syndrome were shown to be genetically linked to epilepsy. Only hypertelorism and digital hypoplasia were associated with phenytoin exposure. The current concept of the syndrome seems to be incorrect; most of the "typical" characteristics are not caused by phenytoin. None of the phenytoin-exposed children had all of the main characteristics of hydantoin syndrome (typical acrofacial features, intellectual deficiency, growth retardation, and microcephaly). The risk of developmental disturbance associated with intrauterine phenytoin exposure seems to be much lower than the 7% to 11% risk of fetal hydantoin syndrome reported earlier.

Pathophysiologic study of chronic infarcts with I-123 isopropyl iodo-amphetamine (IMP): the importance of periinfarct area

Seventeen chronic cerebral infarcts were investigated by a highly sensitive, dedicated brain single photon emission computerized tomography system using 123I-isopropyl iodoamphetamine (IMP) and 133Xe. IMP uptake was measured 10 minutes, 2 hours, and 5 hours after injection, and regional cerebral blood flow was measured with 133Xe. In 4 cases a positron emission tomography system was used to measure the rCBF and the regional metabolic rate of oxygen with C15O2 and 15O2. The results obtained allowed us to identify 2 abnormal zones. One, the "central area," was characterized by a severe decrease in IMP uptake and rCBF averaging 34% and 46% respectively and by a hypodense image on the x-ray computerized tomography scan. The second, the periinfarct or "peripheral area" was characterized by a moderate decrease in IMP uptake and regional cerebral blood flow averaging 13 and 19% respectively; this area extended around the central area and had a normal density on computerized tomography scan. The IMP hypofixation of the peripheral area observed at the 10th minute tended to disappear at the 5th hour. The volume of this area was often found to be quite large, covering more than 30% of a hemisphere whereas the central area did not exceed 25%. Volume appeared to be correlated with the neurological status of the patient. The nature of the peripheral area is not established with certainty. It may be caused by deafferentation of areas not directly affected by the ischemic insult and/or selective ischemic neuronal loss. The results stress the important role played by the peripheral area, which may be useful in establishing the prognosis and evaluating the efficacy of therapy in individual stroke cases.

Obstetric outcome in women with epilepsy

A comparison of 150 pregnancies in women with epilepsy and 150 pregnancies in matched nonepileptic control women showed similar rates of pregnancy-induced hypertension, albuminuria, premature contractions, premature labor, and bleeding in pregnancy. Duration of labor, blood loss at delivery, cesarean section rates, and vacuum extraction rates were also similar among epileptic and control groups. There were five perinatal deaths in the epileptic group and two in the control group. A fetal heart rate tracing during a maternal grand mal seizure showed bradycardia, reduced short-term and long-term variability, and late decelerations suggesting asphyxia. It is concluded that grand mal seizures during pregnancy should be avoided by the use of antiepileptic drugs. Women with epilepsy require antenatal neurological and obstetric follow-up during pregnancy.

[Chemical and pharmacological aspects of cerebral cellular tracers]

Among the iodophenylalkylamines studied and labelled with iodine 125 or iodine 123, N-isopropyl-iodo-amphetamin (IAMP) was selected and proposed as tracer for blood flow, a "chemical embolus" having almost 100% extraction in the brain. A new way of obtaining N-isopropyl-p-iodo-amphetamin is proposed and the easily-applied exchange reaction with iodine 125 or 123 gives a product with a radiochemical purity of more than 96% and an unexchanged radioactive iodine content of less than 1%. The pharmacokinetic study of this product in the Wistar rat showed distribution in three compartments and the appearance of a steady state by the fourth minute. The target organs are the lungs, liver and brain. The latter receives 3% of the radioactivity and the autoradiographic study shows that the early distribution in the brain for IAMP closely equals the blood flow as found by a diffusible indicator. In the first hour, the redistribution is very low and at this time although IAMP is proposed for the study of regional blood flow, it does not exactly determine the flow but rather mirrors cell activity.

Effect of increased bioavailability of phenytoin tablets on serum phenytoin concentration in epileptic out-patients

1. The bioavailability of a brand of phenytoin tablets used in Finland was improved in 1976. In the present retrospective study serum concentrations of phenytoin, measured before and after the change of bioavailability, are compared in 50 epileptic out-patients, who for various reasons used exactly the same dose of phenytoin tablets and of other drugs despite the increased bioavailability of phenytoin. 2. The mean increase of serum phenytoin steady-state concentration was about 70% after the change of bioavailability but there were considerable interindividual differences in the response. The mean increase in serum phenytoin was only 28% in patients with serum phenytoin concentrations 5 microgram/ml or less but the mean increase was 100% in patients with serum phenytoin between 5 and 10 microgram/ml. In patients with serum phenytoin concentrations more than 10 microgram/ml the mean increase in concentration was 60-80% after the improvement of bioavailability. However, in these groups of patients some clinically manifested phenytoin intoxications enforced the patients to the control and to dose reduction obviously before the steady-state concentration of phenytoin was reached. 3. On the basis of our experiences and those reported in the literature some proposals are presented to be considered when the bioavailability of phenytoin or of another drug with a narrow therapeutic range and a dose-dependent kinetics has to be changed.

Antipyretic analgesics in patients on antiepileptic drug therapy

The effect of administration for three days of acetylsalicylic acid (1500 mg/day), phenylbutazone (300 mg/day), paracetamol (1500 mg/day) and tolfenamic acid (300 mg/day) on serum concentrations of phenytoin and carbamazepine were studied in a group of patients on continuous antiepileptic therapy. When measured 10 h after the last dose of the analgesics, the only significant effect was a decrease in total serum phenytoin after three days of phenylbutazone. When six patients on continuous phenytoin therapy took phenylbutazone for two weeks there was at two days an initial decrease, followed by a signficiant increase in total serum phenytoin and a concomitant increase in free phenytoin in serum. Even phenylbutazone was well tolerated by most of the patients. However, its use had to be discontinued on one patient due to obvious signs of phenytoin intoxication, with concomitant increases in the serum free and total phenytoin concentrations.

Fetal heart rate during a maternal grand mal epileptic seizure

Although maternal ingestion of antiepileptic drugs is strongly suspected of causing congenital defects, particularly oral clefts, the effect of epilepsy itself or a combined effect of drug intake and epilepsy have not been excluded as etiological factors. Very little is known about fetal oxygenation during a maternal grand mal epileptic seizure. We describe two cases in which fetal heart rate was recorded during a maternal epileptic seizure during labor. The first fetus became clearly asphyctic as judged from the fetal heart rate recording: immediately after the epileptic seizure there was a 13-minute continuous bradycardia wave with decreased short-term variability. After the bradycardia a phase of tachycardia with decreased short-term and long-term variability occurred. In the other fetus there was only a short period of bradycardia, which was followed by a phase of tachycardia and decreased short-term and long-term variability. Both fetuses were vigorous at birth 43 and 87 minutes, respectively, after the epileptic seizures of their mothers. We conclude that a maternal grand mal epileptic seizure can be ominous to the fetus. It is therefore important that epileptic seizures are controlled by optimal medication throughout pregnancy.

Do the peptide hormones common to intestine and brain participate in the genesis of epilepsy?

It is suggested that the peptide hormones common to the brain and intestine provide a physiological basis to the hypothesis that acute gastroenteritis during the first postnatal month may be associated with spontaneous epileptogenic activity in EEG and lowered seizure threshold in adult age.

Plasma, red cell and cerebrospinal fluid concentrations of myoinositol in patients with severe chronic renal failure

A study was made of 24 patients with severe chronic renal failure; 14 of them were undergoing regular haemodialysis treatment 3 times weekly. Plasma, red-cell and cerebrospinal fluid concentrations of myoinositol were increased in all the patients treated conservatively. The plasma level of myoinositol correlated with the plasma level of creatinine (r = 0.78). The plasma myoinositol level increased more than the CSF and red-cell levels, indicating that the myoinositol in the red cells and the CSF originated mostly in plasma. Dialysis for eight hours produced a fall of about 50% in the level of myoinositol in plasma while the decrease in red-cell myoinositol was negligible. This lead to an osmotic grandient between extra- and intra-cellular myoinositol which was however small in molar terms and did not correlate with symptoms of central neurological disturbances.

Plasma, red cell and cerebrospinal fluid concentrations of mannitol and sorbital in patients with severe chronic renal failure

The concentrations of mannitol and sorbitol in plasma, red cells, cerebrospinal fluid and urine were determined in 24 patients with chronic renal failure; 10 of them were on conservative treatment and 14 were haemodialysed three times weekly. The mannitol concentration was significantly increased in the plasma and the cerebrospinal fluid of the uraemic patients compared with the controls. In six out of ten uraemic patients mannitol clearance values exceeded creatinine clearance values. The plasma concentration of sorbitol was undetectable or very low in all patients and control subjects. Red-cell and cerebrospinal fluid concentrations of sorbitol showed a large individual variation in the uraemic patients on conservative treatment and did not correlate with kidney function. During dialysis the mannitol concentration decreased, leading to a small osmotic gradient between the plasma and the red cells. The changes in the concentration of mannitol during dialysis showed no connection with the symptoms of central nervous disturbance which appeared during dialysis treatment. The red cell sorbitol concentration during dialysis increased by about 20%. There was a correlation (p less than 0.05) between t,e increase in sorbital in cereemic patients.

A new stannous agent kit for labelling red blood cells with 99TCM and its clinical application

99Tcm is chosen for labelling erythrocytes for vascular imaging to take advantage of the physical properties of the radionuclide. A new procedure is described which belongs to the category of pre-treatment methods using a kit. Stannous pyrophosphate is the specific reducing reagent. The technique is easier than already published methods: it consists of adding the above reagent to 2 ml. of heparinized blood, waiting five minutes and discarding the serum after centrifugation, then adding the radioactivity required as 99TcmO4. Labelling yield is superior to 95 per cent. The influence of technetium concentration of the pertechnetate solution on the labeling yield is evaluated and compensated by a slight adjustment of tin concentration when necessary. In vitro and in vivo stability studies show that 99Tcm-labelled red cells are suitable for determination of red cell volume, spleen and placental imaging, particularly in emergencies and in paediatrics.

Technetium-99m labeling by means of stannous pyrophosphate: application to bleomycin and red blood cells

A new technique of technetium labeling using stannous pyrophosphate instead of stannous chloride as reducing agent for pertechnetate has been applied to red blood cells and bleomycin. Results are so encouraging that this technique could be extended to other compounds capable of forming stable complexes with reduced technetium. No saline washes of red cells are necessary before or after the addition of pertechnetate. No purification step is performed after labeling of bleomycin.