Vaccinazioni per l’infanzia ed autismo: un caso accertato negli Stati Uniti

Mercoledì 9 Aprile 2008 - Gli studi clinici hanno fallito nel mostrare un legame tra vaccinazione ed autismo, ma molti genitori di bambini autistici hanno nutrito dubbi su queste conclusioni.

Il Governo americano ha ora ammesso che la vaccinazione può avere arrecato danni ad una bambina di 9 anni, ed ha annunciato che si farà carico delle spese per la cura.
Nel 2000 Hannah aveva 19 mesi ed uno sviluppo normale, quando ricevette 5 iniezioni per la prevenzione di 9 malattie infettive.
Nel 2001 alla bambina è stato diagnosticato il disturbo autistico.
Per il fatto che il padre di Hannah era un neurologo al Johns Hopkins Hospital, la bambina è stata sottoposta ad una serie di esami, che hanno evidenziato un disordine a livello mitocondriale.
Due teorie sono state ipotizzate: la prima che la bambina presentava una sottostante malattia mitocondriale e che la vaccinazione ha slatentizzato, la seconda è che la vaccinazione ha causato questo disordine.
Il Governo ha optato per la prima ipotesi: la bambina aveva una sottostante malattia mitocondriale che è stata aggravata dalla vaccinazione.
Molti dei vaccini che Hannah ha ricevuto contenevano Tiomersale, un preservativo a base di Mercurio.
Negli Stati Uniti, il Tiomersale è stato rimosso dai vaccini somministrati nell’infanzia a partire dal 2001.
Rimane aperto il dibattito sulle vaccinazioni multiple nell’infanzia. ( Xagena Medicina )
Fonte: The New York Times, 2008 - Medicina-Online.net  + vedi Autismo - La prova dei Danni dei Vaccini  +  Autismo dai VACCINI

As in ASD, sensory issues are reported in nearly all cases of mercury toxicity, and serve to demonstrate the similarities between the two conditions.  Paresthesia, or abnormal sensation, tingling, and numbness around the mouth and in theextremities, is the most common sensory disturbance in Hg poisoning, and is usually the first sign of toxicity (Fagala and Wigg, 1992; Joselow et al, 1972; Matheson et al, 1980; Amin-Zaki, 1979).  In Japanese who ate contaminated fish, there was numbnessin the extremities, face and tongue (Snyder, 1972; Tokuomi et al, 1982).  Iraqi children who ate bread experienced sensory changes including numbness in the mouth, hands and feet, and a feeling that there were “ants crawling under the skin.”  These children could still feel a pinprick (Amin-Zaki, 1978).  Loss of position in space has also been noted (Dales, 1972).  Acrodynia sufferers describe excessive pain when bumping limbs, numbness, and poor circulation (Farnesworth, 1997).  One adult acrodynia victimdescribed himself as a boy as “shying away from people wanting to touch me” due to extreme touch sensitivity (Neville Recollection, Pink Disease Support Group).  Iraqi babies exposed to mercury prenatally showed excessive crying, irritability, and exaggerated reaction to stimulation such as sudden noise or when touched (Amin-Zaki et al, 1974 and 1979).

      Movement/Motor Function
Nearly all cases of autism include disorders of physical movement. Movement disturbances have been detected in infants as young as four to six months old who were later diagnosed as autistic: Teitelbaum et al (1998) have observed that these children do not lie, roll over, sit up or crawl like normal infants; impairment in motor control sometimes caused these babies to fall over while sitting, consistently to avoid using one of their arms, or to rest on their elbows for stability while crawling.  Later, when trying to walk their gait was abnormal, and some degree of asymmetry, mostly right-sided, was present in all cases studied.  Kanner noted in several of his subjects the absence of crawling and a failure to assume an anticipatory posture preparatory to being picked up in infancy (Kanner, 1943). Arm flapping, abnormal posture, jumping, and hand-finger mannerisms (choreiform movements) are common (Tsai, 1996).  Many individuals with Asperger’s syndrome are typically characterized as uncoordinated or clumsy (Kugler, 1998).  Other autism movement disorders include praxis (problems with intentional movement), stereotypies, circling or spinning, rocking, myoclonal jerks, difficulty swallowing and chewing, difficulty writing with or even holding a pen, limb apraxia, and poor eye-hand coordination (Caesaroni and Garber, 1991; Gillberg and Coleman, 1992; Filipek et al, 1999).
Like ASD, movement disorders have been a feature of virtually all descriptions of mercury poisoning in humans (Snyder, 1972). Even children prenatally exposed to “safe” levels of methylmercury had deficits in motor function (Grandjean et al, 1998). The movement-related behaviors are extremely diverse: Iraqi infants and children exposed postnatally, for example, developed ataxia that ranged from clumsiness and gait disturbances to an “inability to stand or even sit” (Amin-Zaki et al, 1978). The various movement behaviors are listed more fully in Table VI (Adams et al, 1983; Kark et al, 1971; Pierce et al, 1972; Snyder, 1972; O’Carroll et al, 1995; Tokuomi et al, 1982; Amin-Zaki, 1979; Florentine and Sanfilippo, 1991; Rohyans et al, 1984; Fagala and Wigg, 1992; Smith, 1977; Grandjean et al, 1998; Farnesworth, 1997; Dales, 1972; Matheson et al, 1980; Lowell et al, 1996; O’Kusky et al, 1988; Vroom and Greer, 1972; Warkany and Hubbard, 1953).
Noteworthy because of similarities to movement disorders in autism are reports in the Hg literature of (a) an infant with “peculiar tremulous movements of the extremities which were principally proximal and can best be described as flapping in nature” (Pierce et al, 1972; Snyder, 1972); (b) “jerking movements of the upper extremities” in a man injected with thimerosal (Lowell et al, 1996); (c) “constant choreiform movements affecting the fingers and face” in mercury vapor intoxication (Kark et al, 1971); (d) myoclonal jerks, associated with epilepsy (Amin-Zaki et al, 1978); (e) poor coordination and clumsiness among victims of acrodynia (Farnesworth, 1997); (f) rocking among infants with acrodynia (Warkany and Hubbard, 1953); and (g) unusual postures observed in both acrodynia and mercury vapor poisoning (Vroom and Greer, 1972; Warkany and Hubbard, 1953). In animal studies, cats exposed to mercury by eating fish developed circling movements” (Snyder, 1972), and subcutaneous administration of methylmercury to rats during postnatal development has resulted in postural disorders (O’Kusky et al, 1988).  As summarized in Table V, movement similarities in autism and Hg poisoning are clear.

      Cognition/Mental Function

Nearly all autistic individuals show impairment in some aspects of mental function, even as other cognitive abilities remain intact.  Most individuals may test in the retarded range, while others have normal to above average IQs. These characteristics are true in mercurialism. Moreover, the specific areas of impairment are similar in the two disorders.
The impaired areas in autism are generally in (a) short term or working memory and auditory and verbal memory; (b) concentration and attention, particularly attention shifting; (c) visual motor and perceptual motor skills, including eye-hand coordination; (d) language/verbal expression and comprehension; and (e) using visually presented information when constraints are placed on processing time.  Relatively unimpaired areas include rote memory skills, pattern recognition, matching, perceptual organization, and stimuli discrimination. Higher level mental skills requiring complex processing are typically deficient; these include (a) processing and filtering of multiple stimuli; (b) following multiple step commands; (c) sequencing, planning and organizing; and (d) abstract/conceptual thinking and symbolic understanding (Rumsey & Hamburger, 1988; Plioplys, 1989; Bailey et al, 1996; Filipek et al, 1999; Rumsey, 1985; Dawson, 1996; Schuler, 1995; Grandin, 1995; Sigman et al, 1987).  Younger or more mentally impaired children may have difficulties with symbolic play and understanding object permanence or the mental state of others (Bailey et al, 1996).  Some autistic children are hyperlexic, showing superior decoding skills while lacking comprehension of the words being read (Prizant, 1996). As mentioned before, for most autistic individuals verbal IQ is lower than performance IQ.
As in autism, Hg exposure causes some level of impairment primarily in (a) short term memory and auditory and verbal memory; (b) concentration and attention, including response inhibition; (c) visual motor and perceptual motor skills, including eye-hand coordination; (d) language/verbal expression and comprehension; and (e) simple reaction time. Hg-affected individuals may present as “forgetful” or “confused.” Performance IQ may be higher than verbal IQ. “Degeneration of higher mental powers” has resulted in (a) difficulty carrying out complex commands; (b) impairment in abstract and symbolic thinking; and (c) deficits in constructional skills and conceptual abstraction. One study mentions alexia, the inability to comprehend the meaning of words, although reading of the words is intact (Yeates & Mortensen, 1994; O’Carroll et al, 1995; Pierce et al, 1972; Snyder, 1972; Adams et al, 1983; Kark et al, 1971; Amin-Zaki, 1974 and 1979; Daviset al, 1994; Grandjean et al, 1997 & 1998; Myers & Davidson, 1998; Gilbert & Grant-Webster 1995; Dales, 1972; Fagala and Wigg, 1992; Farnesworth, 1997; Tuthill, 1899; Joselow et al, 1972; Rice, 1997; Piikivi et al, 1984; Vroom and Greer, 1972).  Even children exposed prenatally to “safe” levels of methylmercury show lower scores on selective subtests of cognition, especially in the domains of memory and attention, relative to unexposed controls (Grandjean et al, 1998).  In exposed juvenile monkeys, tests have revealed delays in the development of object permanence, or the ability to conceptualize the existence of a hidden object (Rice, 1996).
Research on mental retardation in autism is contradictory (Schuler, 1995).  The finding that “mental retardation or borderline intelligence often co-exists with autism” (Filipek et al, 1999) is based on using standard measures of intelligence (Gillberg & Coleman, 1992, p.32; Bryson, 1996); other intelligence tests, designed to circumvent the language and attentional deficits of autistic children, show significantly higher intelligence test scores (Koegel et al, 1997; Russell et al, 1999).  One study using such a modified rating instrument has found 20% of autistic children to be mentally retarded (Edelson et al, 1998),rather than the 70%-80% so scored on standard tests.  ASD individuals also show “strikingly uneven scores” on IQ subtests, “unlike other disorders involving mental retardation, in which subtest scores seem to be more or less even” (Bailey et al, 1996).  Also unlike typical cases of mental retardation, which is nearly always noted in the peri- or neonatal periods, most parents of ASD children report infants of seemingly normal appearance and development who were later characterized as mentally retarded on tests.  For example, one study compared early developmental aberrations in mentally retarded children with and without autism.  Findings indicated that, whereas nearly all parents of the non-autistic mentally retarded study group were aware of their child’s impairment by age 3 months, nearly all parents of the autistic children failed to notice any developmental delays or issues until after 12 months of age (Baranek, 1999). Finally, there are several case reports of autistic adults who were labeled mentally retarded as children based on tests, who later “emerged” from their autism and had normal IQs (ARI Newsletter, 1993, review).
As in autism, symptomatic mercury-poisoned victims can present with normal IQs, borderline intelligence, or mental retardation; some may be so impaired as to be untestable (Vroom and Greer, 1972; Davis et al, 1994). When lowered intelligence is found, it is always reported as an obvious deterioration among previously normally functioning people; this includes children exposed as infants or toddlers (Dale, 1972; Vroom and Greer, 1972; Amin-Zaki, 1978).  Once the Hg-exposure source is removed, many (although not all) of these patients “recover” their normal IQ, suggesting that “real” IQ was not affected (Vroom and Greer, 1972; Davis et al, 1994).  Infant monkeys given low doses of Hg, while clearly impaired in visual, auditory, and sensory functions, had intact central processing speed, which has been shown to correlate with IQ in humans (Rice, 1997).

Behaviors

Autism is associated with difficulties initiating and/or maintaining sleep; hyperactivity and other ADHD traits; and self injurious behavior suchas head banging, even in the absence of mental retardation.  Agitation, screaming, crying, staring spells, stereotypical behaviors, and grimacing are common (Gaedye, 1992; Gillberg and Coleman, 1992; Plioplys, 1989; Kanner, 1943; Richdale, 1999; Stores &Wiggs, 1998).  Kanner (1943) made a point of noting excessive and open masturbation in two of the eleven young children comprising his initial cases.  Feeding and suckling problems are typical (Wing, 1980), and restricted diets and narrow food preferences“are the rule rather than the exception” (Gillberg and Coleman, 1992; Clark et al, 1993); some autistics show a preference for salty foods (Shattock, 1997).  Kanner, in his 1943 article, noted feeding problems from infancy, including vomiting and a refusalto eat, in six of the eleven autistic children he described.  There are case studies of anorexia nervosa occurring in ASD patients, as well as an increased likelihood of this eating disorder in families with ASD (Gillberg & Coleman, 1992, p.99).
Humans and animals exposed to mercury develop unusual, abnormal, and “inappropriate” behaviors (Florentine and Sanfilippo, 1991).  Rats exposed to mercury during gestation have exhibited stereotyped sniffing (Cuomo et al, 1984) and hyperactivity (Fredriksson et al, 1996).  “Restlessness” has already been noted, and Davis et al (1994) found poor response inhibition in their human subjects; both of these behaviors are closely associated with ADHD in children. Babies and children with Hg poisoning exhibit agitation, crying for no observable reason, grimacing, and insomnia (Pierce et al, 1972; Snyder, 1972; Kark et al, 1971; Amin-Zaki, 1979; Florentine and Sanfilippo, 1991; Aronow and Fleischmann, 1976).  An 18 month old toddler with otitis media, exposed to thimerosalin ear drops, had staring spells and unprovoked screaming episodes (Rohyans et al, 1984).  Symptoms of acrodynia in babies and toddlers include continuous crying, anorexia and insomnia (Matheson et al, 1980; Aronow and Fleischmann, 1976).  These children were said to bang their heads, have difficulty falling asleep, be irritable, and either refuse to eat or only eat a few foods (Neville Recollection, Pink Disease Support Group Site; Farnesworth, 1997).  The frequent temper tantrums of a previously normal 12year old, poisoned by mercury vapor, included hitting herself on the head and screaming; furthermore, she had extreme genital burning and was observed to masturbate even in front of others (Fagala and Wigg, 1992).  Similarly, priapism, persistent erection of the penis due to a pathologic condition resulting in pain and tenderness, has been noted in boys with mercury poisoning (Amin-Zaki et al, 1978).
Adults with mercury poisoning present with insomnia, agitation, and poor appetite (Tuthill, 1899; Adams et al, 1983; Fagala and Wigg, 1992).  Relative to controls, more adults who had acrodynia in childhood have eating idiosyncrasies, particularly a preference for salty foods to sweet ones (Farnesworth, 1997), possibly because mercury causes excessive sodiumexcretion, as shown in studies of dental amalgam placed in monkeys and sheep (Lorscheider et al, 1995).

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