Clinical presentation of pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections in research and community settings

BACKGROUND

The first cases of pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) were described >15 years ago. Since that time, the literature has been divided between studies that successfully demonstrate an etiologic relationship between Group A streptococcal (GAS) infections and childhood-onset obsessive-compulsive disorder (OCD), and those that fail to find an association. One possible explanation for the conflicting reports is that the diagnostic criteria proposed for PANDAS are not specific enough to describe a unique and homogeneous cohort of patients. To evaluate the validity of the PANDAS criteria, we compared clinical characteristics of PANDAS patients identified in two community practices with a sample of children meeting full research criteria for PANDAS.

METHODS

A systematic review of clinical records was used to identify the presence or absence of selected symptoms in children evaluated for PANDAS by physicians in Hinsdale, Illinois (n=52) and Bethesda, Maryland (n=40). RESULTS were compared against data from participants in National Institute of Mental Health (NIMH) research investigations of PANDAS (n=48).

RESULTS

As described in the original PANDAS cohort, males outnumbered females (95:45) by ∼ 2:1, and symptoms began in early childhood (7.3±2.7 years). Clinical presentations were remarkably similar across sites, with all children reporting acute onset of OCD symptoms and multiple comorbidities, including separation anxiety (86-92%), school issues (75-81%), sleep disruptions (71%), tics (60-65%), urinary symptoms (42-81%), and others. Twenty of the community cases (22%) failed to meet PANDAS criteria because of an absence of documentation of GAS infections.

CONCLUSIONS

The diagnostic criteria for PANDAS can be used by clinicians to accurately identify patients with common clinical features and shared etiology of symptoms. Although difficulties in documenting an association between GAS infection and symptom onset/exacerbations may preclude a diagnosis of PANDAS in some children with acute-onset OCD, they do appear to meet criteria for pediatric acute-onset neuropsychiatric syndrome (PANS).

An open-label trial of riluzole, a glutamate antagonist, in children with treatment-resistant obsessive-compulsive disorder

BACKGROUND

Obsessive-compulsive disorder (OCD) in childhood is often refractory to treatment. Riluzole, a glutamate antagonist, has theoretical support as an alternative pharmacological treatment and has demonstrated possible benefit in some open-label trials in adults with OCD.

METHODS

Six subjects, ages 8-16 years, were enrolled in a 12-week open-label trial of riluzole for OCD symptoms that had resisted prior treatments. OCD symptoms and adverse effects of drug were monitored.

RESULTS

Four of 6 subjects had clear benefit, with reduction of more than 46% (39% overall) on Children's Yale-Brown Obsessive-Compulsive Scale, and "Much Improved" or "Very Much Improved" on the Clinical Global Impressions-Improvement scale. Two subjects had no clinically meaningful change in symptom severity by 12 weeks, but 1 subject improved thereafter. There were no adverse effects of drug sufficient to cause discontinuation or reduction of dose. All subjects elected to continue riluzole after the 12-week trial.

CONCLUSIONS

Riluzole may be beneficial for treatment-resistant OCD in young subjects and seems well tolerated. A placebo-controlled trial of the drug is planned.

Antibiotic prophylaxis with azithromycin or penicillin for childhood-onset neuropsychiatric disorders

BACKGROUND

The acronym PANDAS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections) describes a subgroup of children with obsessive-compulsive disorder and/or tic disorder that experience symptom exacerbations following streptococcal infections. We hypothesized that the prevention of streptococcal infections among children in the PANDAS subgroup would decrease neuropsychiatric symptom exacerbations.

METHODS

Twenty-three subjects with PANDAS were enrolled in a double blind, randomized controlled trial. Antibiotic prophylaxis with penicillin or azithromycin was administered for 12 months. Rates of streptococcal infections and neuropsychiatric symptom exacerbations were compared between the study year and the baseline year prior to entry.

RESULTS

Significant decreases in streptococcal infections during the study year were found with a mean of .1 (.3 SD) per subject, compared to the baseline year with 1.9 (1.2 SD) in the penicillin group and 2.4 (1.1 SD) in the azithromycin group [p<.01]. Significant decreases in neuropsychiatric exacerbations during the study year were also found with a mean of .5 (.5 SD) per subject in the penicillin group and .8 (.6 SD) in the azithromycin group, compared to the baseline year with 2.0 (.9 SD) in the penicillin group and 1.8 (.6 SD) in the azithromycin group [p<.01].

CONCLUSIONS

Penicillin and azithromycin prophylaxis were found to be effective in decreasing streptococcal infections and neuropsychiatric symptom exacerbations among children in the PANDAS subgroup.

Psychiatric disorders in first-degree relatives of children with pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS)

OBJECTIVE

To determine the rates of psychiatric disorders in the first-degree relatives of children with infection-triggered obsessive-compulsive disorder (OCD) and/or tics (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections; PANDAS).

METHOD

The probands of this study were 54 children with PANDAS (n = 24 with a primary diagnosis of OCD; n = 30 with a primary diagnosis of a tic disorder). One hundred fifty-seven first-degree relatives (100 parents [93%] and 57 siblings [100%]) were evaluated for the presence of a tic disorder. One hundred thirty-nine first-degree relatives (100 parents [93%] and 39 of 41 siblings over the age of 6 [95%]) were evaluated with clinical and structured psychiatric interviews to determine the presence of subclinical OCD, OCD, and other DSM-IV Axis I disorders.

RESULTS

Twenty-one probands (39%) had at least one first-degree relative with a history of a motor or vocal tic; 6 mothers (11%), 9 fathers (19%), and 8 siblings (16%) received this diagnosis. Fourteen probands (26%) had at least one first-degree relative with OCD; 10 mothers (19%), 5 fathers (11%), and 2 siblings (5%), received this diagnosis. An additional 8 parents (8%) and 3 siblings (8%) met criteria for subclinical OCD. Eleven parents (11%) had obsessive-compulsive personality disorder.

CONCLUSIONS

The rates of tic disorders and OCD in first-degree relatives of pediatric probands with PANDAS are higher than those reported in the general population and are similar to those reported previously for tic disorders and OCD. Further study is warranted to determine the nature of the relationship between genetic and environmental factors in PANDAS.

Postinfectious and other forms of obsessive-compulsive disorder

The search for subtypes of OCD has led to increased appreciation of the importance of distinguishing early (prepubertal) versus later on-set, and of tic-related versus non-tic related subtypes, as well as postinfectious forms of the disorder. How these apparent typologies relate to each other remains to be elucidated. Careful longitudinal clinical descriptive studies, as well as the ongoing application of genetic, neuroimaging, and immunologic techniques, promise to advance our understanding of how genotype and environmental factors interact to produce the diverse clinical forms of OCD and to point the way to more effective treatment.

A pilot study of penicillin prophylaxis for neuropsychiatric exacerbations triggered by streptococcal infections

BACKGROUND

Some children with obsessive-compulsive disorder (OCD) and tic disorders appear to have symptom exacerbations triggered by group A beta-hemolytic streptococcal infections in a manner that is similar to rheumatic fever and its neurologic variant, Sydenham's chorea. Because penicillin prophylaxis has proven to be effective in preventing recurrences of rheumatic fever, it was postulated that it might also prevent streptococcal-triggered neuropsychiatric symptom exacerbations in children with Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections (PANDAS). These children are identified by five clinical characteristics: presence of OCD or tic disorder, prepubertal onset, episodic symptom course, neurologic abnormalities (i.e., choreiform movements) and streptococcal-triggered symptom exacerbations.

METHODS

Thirty-seven children with PANDAS were enrolled in an 8 month, double-blind, balanced cross-over study. Patients were randomized to receive either 4 months of the active compound (twice daily oral 250 mg penicillin V) followed by 4 months of placebo, or placebo followed by penicillin V. Tic, OCD, and other psychiatric symptoms were monitored monthly. Throat cultures and streptococcal antibody titers were also obtained.

RESULTS

There were an equal number of infections in both the active and placebo phases of the study. There was no significant change seen in either the obsessive-compulsive or tic symptom severity between the two phases.

CONCLUSIONS

Because of the failure to achieve an acceptable level of streptococcal prophylaxis, no conclusions can be drawn from this study regarding the efficacy of penicillin prophylaxis in preventing tic or OCD symptom exacerbations. Future studies should employ a more effective prophylactic agent, and include a larger sample size.

Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections: clinical description of the first 50 cases

OBJECTIVE

The purpose of this study was to describe the clinical characteristics of a novel group of patients with obsessive-compulsive disorder (OCD) and tic disorders, designated as pediatric autoimmune neuropsychiatric disorders associated with streptococcal (group A beta-hemolytic streptococcal [GABHS]) infections (PANDAS).

METHOD

The authors conducted a systematic clinical evaluation of 50 children who met all of the following five working diagnostic criteria: presence of OCD and/or a tic disorder, prepubertal symptom onset, episodic course of symptom severity, association with GABHS infections, and association with neurological abnormalities.

RESULTS

The children's symptom onset was acute and dramatic, typically triggered by GABHS infections at a very early age (mean = 6.3 years, SD = 2.7, for tics; mean = 7.4 years, SD = 2.7, for OCD). The PANDAS clinical course was characterized by a relapsing-remitting symptom pattern with significant psychiatric comorbidity accompanying the exacerbations; emotional lability, separation anxiety, nighttime fears and bedtime rituals, cognitive deficits, oppositional behaviors, and motoric hyperactivity were particularly common. Symptom onset was triggered by GABHS infection for 22 (44%) of the children and by pharyngitis (no throat culture obtained) for 14 others (28%). Among the 50 children; there were 144 separate episodes of symptom exacerbation; 45 (31%) were associated with documented GABHS infection, 60 (42%) with symptoms of pharyngitis or upper respiratory infection (no throat culture obtained), and six (4%) with GABHS exposure.

CONCLUSIONS

The working diagnostic criteria appear to accurately characterize a homogeneous patient group in which symptom exacerbations are triggered by GABHS infections. The identification of such a subgroup will allow for testing of models of pathogenesis, as well as the development of novel treatment and prevention strategies.

Structural alterations of microvascular smooth muscle cells in reduced renal mass hypertension

Loss of microvessels (anatomic rarefaction) occurs in chronic reduced renal mass (RRM) hypertension and is mediated via structural degeneration of vascular smooth muscle (VSM) and endothelial cells. The purpose of the present study was to determine if structural changes occur in VSM cells of the microvessels that remain in the tissue of rats with chronic RRM hypertension. Samples of cremaster muscles were taken from normotensive control rats and rats with acute (3-7 days) and chronic (14-28 days) RRM hypertension (75% reduction in kidney mass with 4% NaCl loading). The samples were fixed in situ and processed for light and electron microscopy. Ultrastructural morphology of VSM cells in terminal arterioles of control animals was normal. Although VSM morphology in many microvessels of RRM hypertensive rats was also normal, some vessels exhibited structural changes that were not present in arterioles of the normotensive animals. The most striking change was the appearance of more extensive dense bodies anchoring the contractile filaments around the outer membrane of the cells. Extreme vasoconstriction was observed in some arterioles of RRM rats as long as 2 weeks after salt loading. Focal areas of VSM cell proliferation were evident. Many of the changes occurring in RRM were detected as early as 1 week after the onset of hypertension. These observations suggest that renal mass reduction-salt loading hypertension is associated with early structural and functional changes in the VSM cells.

Effect of nifedipine on endothelin induced contractions of skeletal muscle arterioles of spontaneously hypertensive rats

Endothelin is a potent vasoactive polypeptide isolated from cultured endothelial cells. However, there are relatively few studies of the action of endothelin on microvessels in vivo. To determine the effects of this compound on arterioles of normotensive and hypertensive rats, endothelin (1 x 10(-12) M to 1 x 10(-8) M) was dissolved in physiological salt solution and superfused over the cremaster muscle of 12-15 week old spontaneously hypertensive rats (SHR) and their normotensive Wistar-Kyoto (WKY) controls. Endothelin caused about a 55% constriction of second order arterioles and complete closure of most third order arterioles and all fourth order arterioles studied. SHR arterioles tended to be more sensitive to endothelin than those of WKY, although this difference was significant for only the third order arterioles. Endothelin induced contractions were significantly inhibited by 10(-6) M nifedipine in both WKY and SHR. These studies demonstrate that endothelin is a potent constrictor of skeletal muscle arterioles, and suggest that activator Ca2+ for endothelin induced contractions of these vessels enters the vascular smooth muscle cells through dihydropyridine sensitive calcium channels.

Piracetam and event-related potentials in dyslexic males

The effect of piracetam on visual event-related potentials (ERP) was investigated in a double-blind placebo-controlled study. Eight- to 12-year-old dyslexic males were randomly assigned to 3.3 g/day of piracetam or matching placebo in two divided doses over a 12-week period. Children performed a vigilance task in which they pressed a key when two alphabetic letters or shapes occurred in sequence. ERPs to letters and shapes, for active and passive responses, were recorded at the vertex and left and right parietal areas of the scalp. Performance measures included letter- and form-hits, misses, commission errors and reaction times. Piracetam increased the amplitude of a late positive component (believed to correspond to P300) at the vertex for letter-hits. Piracetam also increased the latency of this component in both hemispheres, but only for active responses (letter-hits) in the left hemisphere and passive responses (correct rejections and misses) in the right hemisphere. Although piracetam did not significantly affect performance, reaction time to letter-hits was significantly correlated with the latency of the P300 component, suggesting that letters created increased effort or attentional demand on the subjects compared with forms. An early ERP component (P225) also showed increased amplitude to piracetam in both hemispheres and effects were limited to form-hits. These effects were thought to possibly reflect slow negative potentials arising from stimulus anticipation in the CNV-like paradigm. In view of the small sample size, the results were cautiously interpreted as indicating a facilitation of verbal processing mechanisms responsible for analyzing the verbal significance of visual stimuli.

The effects of piracetam in children with dyslexia

Following previous research which suggests that piracetam improves performance on tasks associated with the left hemisphere, a 12-week, double-blind, placebo-controlled study of developmental dyslexics was conducted. Six study sites treated 257 dyslexic boys between the ages of 8 and 13 years who were significantly below their potential in reading performance. Children were of at least normal intelligence, had normal findings on audiologic, ophthalmologic, neurologic, and physical examination, and were neither educationally deprived nor emotionally disturbed. Piracetam was found to be well tolerated in this study population. Children treated with piracetam showed improvements in reading speed. No other effects on reading were observed. In addition, improvement in auditory sequential short-term memory was observed in those piracetam-treated patients who showed relatively poor memory at baseline. It is suggested that longer term treatment with piracetam may result in additional improvements.