Tip Tuesday! Guest Post: APD or ADHD!

Today I have a wonderful guest blog from Smart Speech Therapy, LLC's Tatyana Elleseff,  on differential diagnosis between Auditory Processing Disorder and Attention Deficit Hyperactivity Disorder (hyperactive, inattentive type, and/or combination).

This blog first appeared on June 6, 2011 on Smart Speech Therapy, LLC's blog.  Click on this link to go to original blog post.

Summary: This article explains the difference between attention deficit hyperactivity disorder and auditory processing disorders.  It also outlines the referral process for differential assessment of auditory processing disorders, explains the roles of both audiologist and the speech language pathologist in the assessment and remediation of auditory processing disorders.  Finally, this article cites select assessment instruments sensitive to detection of auditory processing deficit, explains the benefits of multidisciplinary approach to identification and differential diagnosis of processing disorders as well as provides general explanations for parents with respect to treatment approaches to auditory processing disorders.

  

Differential diagnosis of AD/HD and Auditory Processing Disorders in Internationally Adopted School Age Children.

This post originally appeared in the PAL Center International Articles Directory as well as Smart Speech Therapy Blog

Scenario: Corinne is an adorable 8 year old girl with an infectious smile, who has been adopted from Russia at the age of 15 months. She sits quietly by the bookshelf; completely absorbed by the book in her lap, while her distraught mother is quietly telling me in the hallway why Corinne has come to visit me today.   Corinne has numerous listening difficulties. She is very inattentive and frequently mishears verbal messages. She is very distractible and tends to act impulsively at home and in school.  She has trouble organizing her verbal output when speaking and is constantly forgetting what has been told to her, even if it was only moments ago. Corinne has never had a speech and language assessment before, but she does have a documented diagnosis of ADHD, for which she is currently taking medication.  The trouble is that this medication does not seem to be helping Corinne one bit.  She is just as distractible, impulsive and inattentive as she was before. Not only that, but this is not the first medication or the lowest dosage that Corinne has been taking for her ADHD.  According to Corinne’s mother, Corinne’s medications and dosages have been adjusted multiple times by several doctors, but so far it hasn’t really affected anything.  Corinne’s parents’ are at their wit’s end! Corinne is desperately struggling with her studies despite working very hard and getting a lot of help at home, but she is doing so poorly - that her school has been hinting very strongly that Corinne ought to be held back in 3^rd grade.        

Fast forwarding several assessment sessions later, I am not so convinced that ADHD is Corinne’s primary deficit, or even if it’s an appropriate diagnosis for Corinne at all.  Testing has revealed that Corinne has a severe language processing difficulty and requires a referral to an audiologist for a comprehensive auditory processing testing battery.   Corinne’s mom is bewildered at the news: “But no one has suggested anything like this at all before!”

Sadly, Corinne’s case is far from unique.  The incidence and prevalence of AD/HD (the slash is used to denote both subtypes with and without the hyperactivity component) in internationally adopted children is very high and continues to be on the rise. 

What further complicates the situation is lack of valid statistical data. At this time there are no reliable statistics to cite! However, parents of internationally adopted children and those professionals who work with this unique population know just how frequently this label is used.   AD/HD prevalence in internationally adopted children is so highly alarming that it begs a number of important questions:

• “What criteria are currently used for diagnosing AD/HD in internationally adopted children?”
• “Are other disorders with similar symptoms being ruled out before the diagnosis of AD/HD is made?”

Attention Deficit/Hyperactivity Disorder is one of the most commonly diagnosed disorders of childhood.  As a speech language pathologist, who works in a pediatric psychiatric hospital setting, I see many children, including a large number of internationally adopted children, who have the diagnosis of AD/HD in conjunction with other comorbidities including psychiatric disorders as well as speech-language and learning deficits.

However, after the initial screening and assessment period when these children are seen by our multidisciplinary team (psychiatrist, psychologist, nurse, occupational and speech therapists, as well as a learning specialist) in a number of cases, the AD/HD diagnosis is ruled out. 

It is very important to understand that the core symptoms of AD/HD: inattention, hyperactivity, and impulsivity are also the core symptoms in a variety of other disorders, which need to be ruled out in order for the diagnosis of AD/HD to be confirmed with reasonable accuracy. 

The above “core symptoms” are observed in a number of disorders:

• Sensory Processing Dysfunction
• Auditory Processing Disorder
• Mental Retardation
• Hearing Deficits
• Mood Disorders
• Sleep Disorders
• Seizure Disorders
• Acquired Traumatic Brain Injury
• Autistic Spectrum Disorders
• Language Disorders
• Nonverbal Learning Disorder
• Yeast Overgrowth

And this list is by no means exhaustive. 

Since I am a speech language pathologist, in this article I would like to focus on a diagnosis that is most frequently mistaken (or may co-occur) with AD/HD, which is auditory processing disorder (APD), also referred to as Central Auditory Processing Disorder (C/APD).   

Auditory Processing Disorder (APD) is technically not one disorder but a number of disorders, which affect the processing and use of auditory information at the level of the Central Nervous System (CNS).  A child with APD has normal hearing but has trouble recognizing, processing and/or interpreting auditory information.  

The reason why it’s not just a name for one disorder is because according to the 2005 ASHA’s CAPD Technical Report, auditory processing difficulties may affect a number of abilities such as “sound localization and lateralization; auditory discrimination; [and/or] auditory pattern recognition.”  Additionally, the difficulties could be with the “temporal aspects of audition, including temporal integration, temporal discrimination (e.g., temporal gap detection), temporal ordering, and temporal masking; auditory performance in competing acoustic signals (including dichotic listening); and auditory performance with degraded acoustic signals” (ASHA, 2005, CAPD Technical Report).     

These technical terms translate into some of the following auditory processing difficulties for the child: 

• Difficulty processing auditory information efficiently

1. Child may require increased processing time to respond to questions
2. Child may present like they are ignoring the speaker
3. Child may request the speaker to repeat presented information several times
4. Child may not be able to follow long sentences
5. Child will have difficulty keeping up with class discussions in group settings
6. Child’s poor listening abilities under noisy conditions may be interpreted as  “distractibility”

• Difficulty maintaining attention on presented tasks

1. Frequent loss of focus
2. Difficulty completing assignments on their own

·         Poor Short Term Memory - difficulty remembering instructions and directions or verbally presented information 

• Difficulty with phonemic awareness, reading and spelling  

1. Poor ability to recognize and produce rhyming words
2. Poor segmentation abilities (separation of sentences, syllables and sounds)
3. Poor sound manipulation abilities (isolation, deletion, substitution, blending, etc)
4. Poor sound letter identification  abilities
5. Poor vowel recognition abilities

The combination of above factors may result in generalized deficits across the board, affecting the child’s social and academic performance:

·         Poor reading comprehension;

·         Poor oral and written expression

·         Disorganized thinking (e.g., disjointed narrative production)

·         Sequencing errors (recalling/retelling information in order, following recipes, etc)

·         Poor message interpretation

·         Difficulty making inferences

·         Misinterpreting  the meaning of abstract information

Auditory processing difficulties frequently coexist along with AD/HD.   So a child may have both diagnoses AD/HD and APD. However, the child may also be accidentally misdiagnosed with one, instead of the other, or may even have a different diagnosis entirely (e.g., sensory processing dysfunction), which is why a differential diagnosis is absolutely crucial! 

How to initiate an appropriate referral process if you suspect that your school age child has auditory processing difficulties?

If your child is exhibiting any of the above mentioned symptoms, it is very important to address the cause of the problem.  Even though AD/HD and APD may have similar core symptoms, the management of both disorders is quite different. Management of AD/HD may require a number of interventions including behavioral management, medication, and language therapy vs. APD which may require language intervention only, since behavior therapy and stimulant medications used to control AD/HD do not improve the symptoms of APD! (Tillary et al 2000)

To begin, the differential diagnosis of auditory processing disorder falls under the auspices of an audiologist.  However, because many of AD/HD and APD symptoms overlap and manifest as language difficulties, before a referral to an audiologist is made, a speech language pathologist is often consulted first to determine the presence and or extent of language difficulties that affect the child’s listening comprehension, short term memory, attention to verbal messages, and so on.   

A speech language pathologist may also be consulted before the audiologist, if the symptoms in question pertain to a younger child (e.g., 4-5 years of age).  Most auditory processing batteries can only be administered partially when a child is minimally 5 years of age (e.g., SCAN-3C; Pearson Publications) and comprehensively when a child reaches about 7 years of age, due the differences in speed of brain maturation in children.  In contrast, a speech language pathologist can determine much earlier if a child presents with difficulties which may later be diagnosed as APD. In fact one recent test that came out in 2010, the Auditory Skills Assessment (ASA), available from Pearson Publications, screens children as young as 3;6 years of age for early auditory and phonological skills. 

As the result of the above guidelines, some parents have asked me in the past: “If an auditory processing disorder is suspected but only fully diagnosed at 7, does it mean that we have to wait until that age to confirm the diagnosis and only then initiate language therapy?” Absolutely not!

If the assessment indicates that intervention is merited, the speech pathologist can begin addressing specific deficits (e.g., understanding verbal messages, following complex directives, etc), long before the diagnosis of auditory processing disorder can be made, since our aim is to treat the presenting symptoms and not a specific label! 

Furthermore, even after an audiologist confirms the presence of an auditory processing disorder, in the vast majority of cases, the child will be sent back to the speech language pathologist for treatment since treatment of auditory processing deficits falls under the auspices of a speech language pathologist.   

Thus, early detection (e.g., ages 4-5) frequently facilitates successful treatment, remediation, and or mitigation of symptoms.  Early treatment may also decrease symptom severity (e.g., mild-moderate auditory processing disorder vs. severe auditory processing disorder) by the time the child is tested by an audiologist at an older age (e.g., age 8). 

After the initial referral is made, and depending on the nature of deficits (e.g., attention, processing, phonological awareness, memory, etc) a speech pathologist may chose to use a number of language testing instruments, sensitive to various auditory processing components.

Below are just several of the popular screening and testing instruments which may be used by a speech language pathologist in order to determine whether a referral for a comprehensive auditory processing assessment battery with an audiologist is merited. 

·         The Listening Inventory (TLI) (2005) available from Academic Therapy Publications

·         Differential Screening Test for Processing (DSTP) (2006)*

·         Dynamic Screening for Phonological Awareness (DSPA) (2010)*

·         Test of Auditory Processing Skills-3 (2005)**

·         The Listening Comprehension Test-2 (LCT-2) (2006)*

·         The Listening Comprehension Test Adolescent (LCT-A) (2009)*

·         Phonological Awareness Test -2 (PAT-2) (2007)*

·         Comprehensive Test of Phonological Processing (CTOPP) (1999)**

·         Lindamood Auditory Conceptualization Test-3 (LAC-3) (2004)**

*Denotes instruments available from Linguisystems

** Denotes instruments available from multiple publishers such as Linguisystems, Pearson Publications, and/or Super Duper Publications

Please note that a speech language pathologist does not have to use the above tests in order to refer the child for an auditory processing assessment battery.  He/she can select the testing subtests from a number of commonly used language testing instruments such as Clinical Evaluation of Language Fundamentals-4 or Test for Auditory Comprehension of Language-3 (Pearson Publications) in order to test the affected areas of difficulty (e.g., listening comprehension, following directions, etc). 

It is also important to know that speech language pathologists are testing language processing deficits only!  The terms auditory processing and language processing are frequently used interchangeably but - they are NOT synonymous!  As mentioned before auditory processing refers to neural processing of auditory stimuli at the level of the central nervous system, only.  In contrast, language processing deficits may have a variety of causes including global disorders such as mental retardation or autism spectrum disorders. 

So, the SLP will test the child’s language abilities in order to determine if their testing results are indicative of deeper auditory processing deficits.  If they are, and the child’s age is appropriate, then the child will need to see an audiologist who will first perform a routine hearing test to rule out hearing impairment and then if the hearing is normal, the audiologist will administer the auditory processing testing battery.

What is the role of audiologist in the assessment of auditory processing disorders?

• An audiologist is the ONLY professional who diagnoses auditory processing disorders.
• An audiologist is the ONLY professional who is responsible for describing auditory processing deficits diagnosed during the above assessment.
• The audiologist is EXPECTED to suggest treatment and management strategies for school and home accommodations, which are specific to the child’s unique deficits.
• An audiologist MAY provide auditory processing remediation to the child but TYPICALLY he/she will refer the child to a speech language pathologist for further treatment.
• Subsequent to receiving auditory processing intervention, the child will go back to the audiologist (usually after 1 year) in order to receive an auditory processing reassessment battery.
• The child may continue to receive yearly reassessments until the audiologist determines that further assessments/treatments are no longer necessary.  

Audiological testing battery differs from speech language testing battery. Most audiological tests are administered in sound-proof booths and involve the attention and response to signals/tones in addition to attention and response to recorded words, word pairs, and sentences (in contrast to live voice) in the absence and presence of background noise.   Based on presenting symptoms an audiologist will determine what combinations of tests need to be administered. 

After testing is completed it is very important that parent request that the audiologist outline confirmed deficits, suggest treatment hierarchy with goals and objectives as well as make recommendations for school and home accommodations which will be specific to the child’s unique deficits.

This is especially important because much of the terminology used by audiologists may not be familiar to many school based speech language therapists much less parents who are attempting to interpret the report. Therefore, it is important that an audiologist clearly explain what the deficits are and what needs to be done. 

This is necessary in order to avoid confusion regarding the meaning of terms as well as to avoid generalized and unnecessary interventions. For example, the deficits pertaining to term “tolerance fading memory” should be explained as difficulties with speech interpretation in the presence of background noise as well as difficulty with short term memory.  Moreover, it is also important to caution parents that the generic recommendation of an FM system (frequency modulation system) is not applicable to all children with auditory processing deficits but only to those who have been accurately diagnosed with auditory sensitivity and/or auditory distractibility. Similarly, not all parents of children with auditory processing disorders need to rush out to purchase “Earobics” (www.earobics.com) or “Lindamood-Bell” (www.lindamoodbell.com) software programs especially because these phonological awareness programs and their levels of difficulty may not be necessarily applicable to many children with APD symptoms. 

Parents should also be wary of recommendations heavily emphasizing specific costly software or remediation programs (to the exclusion of all other interventions), since not all recommendations are based on scientific research and evidence. Therefore it’s very important to research the efficacy and effectiveness of these products and programs on the ASHA (American Association of Speech Language and Hearing Science) website.

I also want to reemphasize again that even after the diagnosis of C/APD has been confirmed, it may be necessary to revisit the child’s remaining symptoms once more in order to reassess the continued applicability of AD/HD diagnosis and use of medications as well as to rule out the presence of additional comorbidities.   

On such occasions, I have found that The Listening Inventory (TLI) screening instrument is a very helpful tool for making additional referrals.  This questionnaire, which can be filled out by parents AND teachers in as little as 15 minutes, has the users rating the child’s difficulties in 6 areas: linguistic organization, decoding/language mechanics, attention/organization, sensory/motor, social/behavioral, and auditory processes.  After all the statements are rated and the index scores are calculated, many parents are often surprised by the results.  Oftentimes the difficulties they interpret as being social behavioral may actually be the result of sensory/motor impairments, which require an assessment by an occupational therapist. 

This is why the multidisciplinary approach to identification, differential diagnosis, and management of disorders like AD/HD and/or C/APD is so important.  Just one individual assessment, be it psychological, occupational, or audiological, CANNOT reliably determine accurate diagnosis to the exclusion of all others, especially when the diagnostic criteria is based on generalized symptomology (symptoms fit several diagnoses).

To learn more about auditory processing disorders please visit the ASHA website at www.asha.org and type in your query in the search window located in the upper right corner of the website. To find professionals specializing in assessment (audiologist) and treatment (speech language pathologist) of auditory processing disorders in your area please visit: http://asha.org/proserv/. 

References:

·         American Speech-Language-Hearing Association. (2005). (Central) Auditory Processing Disorders [Technical Report]. Available from www.asha.org/policy.

·         Lucker, J.R. (2007). History of Auditory Processing Disorders in Children. In D. Geffner and D. Ross-Swain, Auditory Processing Disorders for Speech-Language Pathologists San Diego: Plural Publishers.

·         Tillery et al. (2000) Effects of Methylphenidate (Ritalin) on Auditory Performance in Children With Attention and Auditory Processing Disorders. Journal of Speech Language and Hearing Research 43, 893-901

Bio:  Tatyana Elleseff MA CCC-SLP is a bilingual SLP with a full time hospital affiliation as well as private practice in Central, NJ. She specializes in working with multicultural, internationally and domestically adopted as well as at-risk children with complex communication disorders. She presents workshops for a number of medical, academic, and non-profit organizations and writes articles for various specialized publications.  For more information visit her website and blog @ www.smartspeechtherapy.com/blog/