Benign intracranial hypertension (pseudotumor cerebri). Review and report of 18 cases

Markedly discordant hypophosphatasia in a young girl

Hypophosphatasia (HPP) is the inborn-error-of-metabolism from deactivating mutation(s) of ALPL, the gene that encodes the cell surface "tissue-nonspecific" isoenzyme of alkaline phosphatase (TNSALP). HPP's "biochemical signature" comprises low serum alkaline phosphatase activity together with elevated plasma levels of the TNSALP natural substrates phosphoethanolamine (PEA), pyridoxal 5'-phosphate (PLP), and inorganic pyrophosphate (PPi). Excess extracellular PPi (ePPi) inhibits mineralization and affected children prematurely shed deciduous teeth and often suffer weakness and rickets. Yet, HPP severity is greatest among all dento-osseous disorders and not fully explained by autosomal dominant versus autosomal recessive inheritance involving >470 ALPL mutations. Discordance of HPP phenotype sometimes manifests even among full siblings sharing an identical ALPL genotype. Herein, a girl's markedly discordant HPP featured at presentation life-threatening hypercalcemia, failure-to-thrive, and renal compromise. Subsequent pseudotumor cerebri syndrome caused blindness, and then craniosynostosis required cranial vault reconstruction. However, she was not deformed, had moderate hypophosphatasemia, normal plasma PLP level, and mild radiographic features of HPP rickets. Elevated plasma N-terminal parathyroid hormone-related protein (PTHrP) suggested malignancy, but corrected after kidney transplantation. HPP was diagnosed when whole exome sequencing revealed heterozygous ALPL c.1034C>T, p.A345V reported in mild pediatric HPP and transmitted by her mother who considered herself well. Genes conditioning ePPi formation and underlying other skeletal diseases were intact. Hypercalcemia, unresponsive to bone antiresorptive drugs, corrected promptly with asfotase alfa TNSALP supplementation therapy. Her markedly discordant findings highlight genotype/phenotype plasticity for pediatric HPP, and her clinical course importance for early diagnosis.

Infantile Idiopathic Intracranial Hypertension: A Case Study and Review of the Literature

Idiopathic intracranial hypertension, or pseudotumor cerebri, is an increase in cerebrospinal fluid pressure of unknown etiology. It is mostly seen in adults, less frequently in adolescents, rarely in younger children. Only 5 infants meeting idiopathic intracranial hypertension criteria have been mentioned in the literature. We report a case of a previously healthy 9-month-old boy who presented with irritability, decreased appetite, and a bulging fontanelle. Computed tomography (CT) head imaging and cerebrospinal fluid studies revealed normal results. The patient's symptoms transiently resolved after the initial lumbar puncture, but 11 days later, his fontanelle bulged again. A second lumbar puncture revealed an elevated opening pressure of 35 cmH₂O and led to a diagnosis of idiopathic intracranial hypertension in accordance with the modified Dandy Criteria. Treatment with acetazolamide at a dose of 25 mg/kg/d was initiated and the patient remained symptom-free for 6 weeks, followed by another relapse. His acetazolamide dose was increased to 37 mg/kg/d, with no further relapses to date. A diagnosis of idiopathic intracranial hypertension is challenging in infants, because the patients cannot yet verbalize typical idiopathic intracranial hypertension-related symptoms such as positional headaches, diplopia, or pulsatile tinnitus. Furthermore, it is more difficult to assess papilledema in that age group. If undetected and untreated, idiopathic intracranial hypertension may result in permanent visual deficits. Little is known about idiopathic intracranial hypertension in infants, and age-specific treatment guidelines are lacking. We discuss this rare case of infantile idiopathic intracranial hypertension and provide a review of the literature, including an overview of disease characteristics and outcomes of idiopathic intracranial hypertension in this very young age group.

Idiopathic intracranial hypertension presenting with isolated unilateral facial nerve palsy: a case report

BACKGROUND

Idiopathic intracranial hypertension, also known as pseudotumor cerebri, is a disorder characterized by increased intracranial pressure of unclear pathogenesis in the absence of other structural and obstructive lesions that is predominantly, although not exclusively, seen in obese women of childbearing age. Patients with idiopathic intracranial hypertension commonly present with a headache, transient visual obscurations, and intracranial noises with some cranial nerves occasionally involved, most commonly CN VI. We report idiopathic intracranial hypertension presenting with isolated complete unilateral facial nerve palsy, as the sole cranial nerve involved, which is a presentation rarely reported in the literature.

CASE PRESENTATION

A 40-year-old Hispanic woman with a history of obesity and hypertension presented to our emergency department complaining of bifrontal headache for 3 days associated with nausea, vomiting, transient visual disturbances, and a picture of right-sided cranial nerve VII palsy. Her neurologic examination including other cranial nerves was otherwise normal, but a fundus examination revealed bilateral grade II papilledema. Imaging studies ruled out structural and obstructive lesions as possible causes of her symptoms and lumber puncture results were unremarkable except for an increased opening pressure. She was then started on prednisone and acetazolamide. Two days later, she reported a dramatic improvement in both headache and facial nerve palsy.

CONCLUSIONS

Idiopathic intracranial hypertension should be suspected in obese young women presenting with headache and transient visual complaints and some cranial nerve abnormalities. Idiopathic intracranial hypertension is a diagnosis of exclusion and imaging studies should always be performed to rule out other structural and obstructive lesions. In this case report, we aimed to draw attention to the possibility of idiopathic intracranial hypertension presenting with unilateral cranial nerve VII palsy as the only cranial nerve involved, which needs a high index of suspicion by clinicians. The mechanisms of cranial nerve VII palsy in idiopathic intracranial hypertension are not well understood and prompt further investigation.

Intracranial Hypertension in Children: Etiologies, Clinical Features, and Outcome

This retrospective study aimed to describe the clinical presentations, possible causes, and outcomes of children with idiopathic intracranial hypertension who presented to the authors' clinic. The mean age at onset of symptoms in the authors' cohort of 19 children was 6 years (range: 7 months to 12 years). Most patients (90%) were under 11 years old and (84.2%) symptomatic. The probable cause was identified in 7/19 (37.0%) patients. The most common cause was vitamin D deficiency (26.3%). Other associated probably coincidental comorbidities included sinusitis (5/19, 26.3%), hypophosphatasia (1/19), Pyle disease (1/19), and measles vaccine (1/19). Apart from 2 patients who required lumboperitoneal shunt, the cerebrospinal fluid pressure returned to normal in all patients within a period of 6 weeks to 1 year (average, 5 months). Of those who followed up with the authors' ophthalmologist, 30.7% developed optic atrophy or pallor; 75% of these patients had previous ocular comorbidities.

The role of aquaporin-1 in idiopathic and drug-induced intracranial hypertension

Idiopathic intracranial hypertension is a common disorder affecting mainly healthy, young, overweight women. The pathogenesis of this condition is unknown, but it has been shown to follow treatment with several compounds including corticosteroids and vitamin A derivatives. This paper will offer a novel hypothesis and insight on the pathogenesis of drug induced intracranial hypertension following a review and analysis of the literature. Both corticosteroids and vitamin A derivatives have been shown to upregulate the expression of aquaporin 1, a water channel protein. Aquaporin 1 is widely distributed in the human brain and is associated with water secretion into the subarachnoid space. Aquaporin 1 was also shown to participate in the regulation of weight. Agents used for treating idiopathic intracranial hypertension reduce aquaporin 1 expression. Based on these observations, we propose that aquaporin 1 has a pathogenetic role in drug induced idiopathic intracranial hypertension. Over expression of this gene causes increased intracranial pressure, and downregulation reduces pressure and alleviates the symptomatology and complications of idiopathic intracranial hypertension.

Hypophosphatasia presenting with pyridoxine-responsive seizures, hypercalcemia, and pseudotumor cerebri: case report

Hypophosphatasia (HPP) is an inborn error of metabolism characterized by defective bone mineralization caused by a deficiency in alkaline phosphatase (ALP) activity due to mutations in the tissue-nonspecific ALP (TNALP) gene. The clinical expression of the disease is variable. Six forms of HPP are identified according to age at presentation and clinical features. Patients with the infantile form are normal at birth. First symptoms appear within the first 6 months of life. Along with skeletal findings, HPP patients may present with hypercalcemia, seizures, pseudotumor cerebri, and pulmonary insufficiency. Seizures in HPP are refractory to conventional antiepileptic drugs, but are responsive to pyridoxine. Herein, we report a case of HPP who presented with pyridoxine-responsive seizures in the early neonatal period and was found to have hypercalcemia, skeletal demineralization and increased intracranial pressure.

Hypophosphatasia associated with pseudotumor cerebri and respiratory insufficiency

We report a 3-month-old male with infantile hypophosphatasia who later developed Pseudotumor cerebri. At the age of 3 months, he was referred to our hospital because of pneumonia and respiratory insufficiency. He had short extremities, and radiographs of the bones were consistent with lack of metaphyseal mineralization and bowed lower extremities. Vomiting and bulging fontanelle developed 3 months after admission, and CSF opening pressure was notably high at 430 mm/H2O. Hypophosphatasia is a very rare cause of pseudotumor cerebri. This report is the first case where PTC is associated with hypophosphatasia and responded well to corticosteroid therapy.

Visual failure without headache in idiopathic intracranial hypertension

AIM

To determine the differences in outcome in a group of children with idiopathic intracranial hypertension (IIH) who do not present with headaches.

METHODS

Differences in epidemiological and aetiological factors, clinical presentation, and visual outcome were investigated in children with a diagnosis of IIH presenting with and without headaches to the Paediatric Neurology and Paediatric Ophthalmology Services at Guy's & St Thomas' Hospitals NHS Trust between 1997 and 2002.

RESULTS

Compared to the 29 children with headaches, the 12 children in the non-headache group were younger (7.3 v 9.5 years), presented with more neurological signs (33% v 10%), and were more likely to present with severe visual failure (33% v 4%), with a tenfold increased risk of an enlarged blind spot or field defects (50% v 5%). Permanent visual failure affected a third of all children in the non-headache group, but was rare in children presenting with headaches (33% v 3%), with one patient registered blind and two severely visually impaired.

CONCLUSION

The management of IIH is difficult in the absence of headache. Visual surveillance is vital. These children were treated with an aggressive management programme to reduce cerebrospinal fluid pressure by repeated lumbar puncture, medication, and early surgical intervention if required. Non-invasive monitoring techniques might contribute to a better understanding of the natural history of IIH, improved management, and visual outcome.

Idiopathic "benign" intracranial hypertension: case series and review

Idiopathic "benign" intracranial hypertension is an uncommon but important cause of headache that can lead to visual loss. This study was undertaken to review our experience in the diagnosis and management of idiopathic intracranial hypertension, giving special attention to treatments used. A retrospective chart review was conducted on 32 patients diagnosed with idiopathic intracranial hypertension between 1984 and 1995. Subjects included 23 females and ranged in age from 2 to 17.5 years. Headache was the most common symptom, followed by nausea and vomiting, double vision, and visual loss. Papilledema was the most common sign. Others were VIth cranial nerve palsy and compromised visual acuity at or within 3 months of presentation. Management included administration of acetazolamide or corticosteroids, lumboperitoneal shunt, optic nerve fenestration, and repeat lumbar puncture. Treatment combinations were used in 40% of cases. During follow-up, headache, papilledema, and decreased visual acuity persisted for longer than 10 months in a significant number of patients. We conclude that idiopathic intracranial hypertension causes significant short- and long-term morbidity with no proven effective treatment available. A prospective study is needed to establish the indications for treatment and the efficacy of the treatments used.

Idiopathic intracranial hypertension in prepubertal pediatric patients: characteristics, treatment, and outcome

PURPOSE

To report the features of idiopathic intracranial hypertension in prepubertal children, with emphasis on presentation, treatment, and outcome.

METHODS

We retrospectively reviewed the charts of all patients 11 years and younger diagnosed with idiopathic intracranial hypertension at two university-affiliated medical centers. Inclusion critera included papilledema, normal brain computed tomography or magnetic resonance imaging, cerebrospinal fluid pressure greater than 200 mm H2O, normal cerebrospinal fluid content, and a nonfocal neurologic examination except for sixth nerve palsy. Patients with concomitant systemic illness were excluded.

RESULTS

Of the 10 patients, four were girls and six were boys. Only one patient was obese. The most common presenting symptoms were stiff neck (four patients) and diplopia (four patients), and the most common presenting sign was strabismus (eight patients). Six of eight patients with strabismus had abducens nerve palsy (four bilateral), one patient had a sensory exotropia, and one had a comitant esotropia. Visual field abnormalities were present in 11 of 13 eyes (85%), and severe visual loss resulting in no light perception vision occurred in one eye of one patient. Nine patients were treated medically, four with a combination of prednisone or dexamethasone and acetazolamide and five with acetazolamide alone. One patient in this group also required a lumboperitoneal shunt. One patient was treated with lumbar puncture only. Resolution of papilledema occurred rapidly in all patients, with a mean of 4.7 +/- 2.6 months. Resolution of sixth nerve palsy also occurred rapidly in four of six patients in a mean of 1.6 +/- 1.2 months. One patient required strabismus surgery for persistent esotropia and one was lost to follow-up.

CONCLUSIONS

Idiopathic intracranial hypertension in prepubertal children is rare and is different than the disease in adults. In our series, there appeared to be no sex predilection, and obesity was uncommon. Children are likely to present with strabismus and stiff neck rather than headache or pulsatile tinnitus. Both papilledema and sixth nerve palsy resolved rapidly with treatment. However, children can sustain loss of visual field and visual acuity despite treatment.

Pseudotumor cerebri in children

PURPOSE

Demographic and outcome data in the era of modern neuroimaging are needed to describe pseudotumor cerebri in children.

METHODS

We reviewed the medical records of children less than 18 years old who were diagnosed with pseudotumor cerebri between 1977 and 1997. We defined pseudotumor cerebri as (1) increased intracranial pressure, (2) normal or small ventricles, and (3) normal cerebrospinal fluid composition. The condition might be idiopathic or the result of a nontumor etiology.

RESULTS

Thirty-seven patients had an initial diagnosis of pseudotumor cerebri. Two patients were subsequently diagnosed with a central nervous system malignancy and were excluded from further analysis. The remaining 35 patients included 10 patients with idiopathic pseudotumor cerebri and 25 patients with disorders reported to be associated with pseudotumor cerebri. The mean age was 10.6 years with a range of 3 to 17 years. Twenty patients (57%) were female and 13 patients (37%) were obese. At presentation 4 patients had a visual acuity less than 20/40 in the best eye and 10 patients had visual field deficits. Seventeen patients (49%) had cranial nerve deficits, all of which resolved with normalization of the intracranial pressure. Follow-up data were obtained on 30 patients. Only one patient had a final visual acuity less than 20/40 in the best eye, whereas six patients had residual visual field deficits. Ten patients (33%) had optic nerve atrophy.

CONCLUSIONS

There was no gender predominance, and associated etiologic factors were common in these children with pseudotumor cerebri. Permanent visual loss occurs in some children with pseudotumor cerebri. Quantitative perimetry and optic nerve examination were more sensitive than visual acuity determination in detecting damage to the visual sensory system. In rare instances the patient diagnosed with pseudotumor cerebri will be found after extended follow-up to harbor an intracranial neoplasm.

Pediatric pseudotumor cerebri: descriptive epidemiology

OBJECTIVE

To determine the epidemiological profile for pediatric pseudotumor cerebri.

METHODS

A retrospective case series was identified from a geographically limited region of 205,765 children aged 2-15 years at the only tertiary care pediatric hospital with all pediatric neurologists and ophthalmologists. Health records identified 35 children with ICD9 code 348.2 (benign intracranial hypertension) presenting between April 1, 1979 and March 31, 1994. After chart review, 29 cases were identified which satisfied modified Dandy's diagnostic criteria for pseudotumor cerebri.

RESULTS

The 29 cases ranged in age from 3-15 years. The annual incidence of symptomatic disease was 0.9 per 100,000 children (95% CI 0.6, 1.4). Cases were 2.7 times more likely to be female (21/29, X2 p = .01) and twice as likely to be adolescent (age 12-15 years), (X2 p = .04). Based upon these distinctions, the following estimates of age and sex specific disease incidence were derived (based upon 100,000 child years of exposure): male age 2-11 years: 0.4; male age 12-15 years: 0.8; female age 2-11 years: 1.1; female age 12-16 years: 2.2.

CONCLUSIONS

These data appear to be unique for its the estimation of age and sex specific incidence rates for pediatric pseudotumor cerebri.

The light-flash-evoked response as a possible indicator of increased intracranial pressure in hydrocephalus

Surgical treatment of infantile hydrocephalus by shunt implantation may result in suboptimal intracranial pressure. Major neurological impairments and death are usually prevented by shunt treatment, but minor sequelae may persist or develop. The introduction of adjustable shunts has improved the possibilities of optimizing shunt function and minimizing the risk of such impairments. However, it is still impossible to determine the intracranial pressure without invasive measurements. Clinical findings and procedures such as computed tomography (CT) are not always enough to allow a conclusion as to whether a child's signs and symptoms are the result of suboptimal intracranial pressure (shunt dysfunction) or are of another etiology. With the aim of reducing the number of invasive pressure measurements and CT scans, we investigated the effect of increased intracranial pressure on the visual evoked response (VER). Binocular light flash stimuli of supramaximal intensity were used and VER recordings were performed from Oz and Cz. The VER results from a group of 31 infants and children with hydrocephalus and 2 children with pseudotumor cerebri were compared with responses from a control group of 35 healthy children. The results show that a subpotential, P' (P-prime), usually just preceding P1 (P100), had an increased latency ( > 96 ms) in all hydrocephalic children before surgery. The P' latency in this group was usually even above 110 ms. The latencies of other VER potentials were also increased but not as consistently as P'. After surgical intervention the VER latencies decreased and usually normalized. The P' latency in four children in the control group was just above the borderline latency, but was less than 110 ms.(ABSTRACT TRUNCATED AT 250 WORDS)

Idiopathic intracranial hypertension associated with tetracycline use in fraternal twins: case reports and review

Fraternal twin sisters developed idiopathic intracranial hypertension (IIH) shortly after beginning tetracycline for treatment of acne. We reviewed from the literature 19 familial cases of IIH and 37 cases of IIH associated with tetracycline usage. Among the 37 combined adult and pediatric cases, 26 of 37 had resolution of signs or symptoms of IIH within hours to days of stopping the antibiotic, and rapid recurrence with reinitiation of drug occurred in 4 of 37. We suggest that these cases may be tetracycline-induced, may be related to an underlying genetic susceptibility, and support the notion of multifactorial etiologies for IIH.

Idiopathic intracranial hypertension in children: the Iowa experience

Idiopathic intracranial hypertension is an uncommon condition in children and is seen only about once a year in a large referral hospital. Sex incidence is equal, and obesity is a feature in about one third of patients. This article reviews the 30-year experience in an institution where idiopathic intracranial hypertension in adults has been extensively studied. Symptomatic causes of intracranial hypertension and both medical and surgical therapeutic options are reviewed.

Pediatric pseudotumor cerebri (idiopathic intracranial hypertension)

This review focuses on the features of pseudotumor cerebri in the pediatric age group. There is no sex predilection in children, and obesity does not appear to be an important factor. Infants and young children may present with irritability, apathy, or somnolence, rather than headache. Dizziness and ataxia may also occur. Papilledema is infrequently noted in pediatric patients if the fontanelles are open or the sutures are split. Pre-adolescents appear more likely than adults or adolescents to have manifestations of their pseudotumor cerebri other than headache and papilledema, including lateral rectus pareses, vertical strabismus, facial paresis, back and neck pain. Among the etiologies that are particularly pertinent to children are tetracycline therapy, malnutrition or renutrition, and the correction of hypothyroidism. Children with pseudotumor cerebri are at risk for visual loss and their visual function must be closely monitored. Surgical intervention is imperative when vision is threatened.

Benign intracranial hypertension in childhood: a review of 23 patients

Twenty-three patients with benign intracranial hypertension (BIH) were seen at the Royal Alexandra Hospital for Children, Sydney over an 18 year period to 1988. Age at presentation ranged from 6 months to 13 years and 5 months. The female to male ratio was 2.3:1. The aetiological factors (sometimes multiple) included: chronic middle ear infection, 30%; dural sinus thrombosis, 22%; head injury, 13%; Vitamin A overdosage, 4%; tetracycline exposure, 4%; and no apparent cause, 43%. Headache was the most common presenting symptom occurring in 91% of patients, followed by vomiting in 65% and blurred or double vision in 57%. Papilloedema occurred in 96% of patients, abducens palsy was noted in 48% and visual impairment in 45%. All patients improved clinically after treatment, one with lumbar puncture only. Of 17 patients treated with steroids, 10 patients recovered and seven patients went on to lumboperitoneal shunt. Two patients recovered with steroid and diuretic treatment. Of two patients initially treated with diuretics only, one recovered and one subsequently required a shunt. Only one patient was initially treated with a lumboperitoneal shunt. Three of the shunted patients had shunt block requiring revision. None had permanent visual loss or other significant sequelae. The visual prognosis of BIH in childhood is good. In view of the relatively high complication rate of steroids and shunting, a controlled comparison of steroid vs acetazolamide/diuretic therapy should be undertaken.

Idiopathic intracranial hypertension (pseudotumor cerebri) in pediatric patients

Improved evaluation of visual features of idiopathic intracranial hypertension in pediatric patients has resulted in the demonstration of optic neuropathy which may be reversible. A wide variety of etiologic associations should be investigated to provide definitive therapy; however, nonspecific means often will be required to lower intracranial pressure. It is hoped that a double-blind controlled trial of medical therapies and another for surgical therapies will be conducted to elucidate optimum management of this condition.

Pseudotumor cerebri and nutritional rickets

A bulging fontanelle due to benign increased intracranial pressure is not generally recognized as a manifestation of nutritional rickets but should be considered in the appropriate clinical setting. Two children who we saw presented with bulging anterior fontanelles were found to have pseudotumor cerebri in association with nutritional rickets.

Steroid-induced benign intracranial hypertension

A 41-year-old man whose systemic lupus erythematosus (SLE) had been successfully treated for 15 months with a daily maintenance dose of 5 mg prednisolone, developed benign intracranial hypertension (BIH) when the steroid was increased to 60 mg daily for recrudescence of SLE symptoms. The BIH remitted when the steroid was discontinued.

Pseudotumour cerebri associated with minocycline therapy for acne

A case of pseudotumour cerebri (PTC) in a 13-year-old girl is reported. This patient experienced menarche seven months before presentation, and subsequently developed acne which necessitated antibiotic therapy. She had been treated with minocycline hydrochloride (100 mg twice a day) for two months before admission to hospital. The role of minocycline therapy associated with menarche in the aetiology of PTC is discussed.