Progressive nonfluent aphasia

Progressive nonfluent aphasia (PNFA) is one of three clinical syndromes associated with frontotemporal lobar degeneration. PNFA has an insidious onset of language deficits over time as opposed to other stroke-based aphasias, which occur acutely following trauma to the brain. The specific degeneration of the frontal and temporal lobes in PNFA creates hallmark language deficits differentiating this disorder from other Alzheimer-type disorders by the initial absence of other cognitive and memory deficits. This disorder commonly has a primary effect on the left hemisphere, causing the symptomatic display of expressive language deficits (production difficulties) and sometimes may disrupt receptive abilities in comprehending grammatically complex language.[1]

Presentation

The main clinical features are signature language progressive difficulties with speech production. There can be problems in different parts of the speech production system, hence patients can present with articulatory breakdown, phonemic breakdown (difficulties with sounds) and other problems. However, it is rare for patients to have just one of these problems and most people will present with more than one problem. Features include:

• Hesitant, effortful speech
• Apraxia of speech
• Stutter (including return of a childhood stutter)
• Anomia
• Phonemic paraphasia (sound errors in speech e.g. 'gat' for 'cat')
• Agrammatism (using the wrong tense or word order)

As the disease develops, speech quantity decreases and many patients become mute.

Cognitive domains other than language are rarely affected early on. However, as the disease progresses, other domains can be affected. Problems with writing, reading, and speech comprehension can occur, as can behavioural features similar to frontotemporal dementia.

Diagnosis

Imaging studies have shown differing results which probably represents the heterogeneity of language problems than can occur in PNFA. However, classically atrophy of left perisylvian areas is seen. Comprehensive meta-analyses on MRI and FDG-PET studies identified alterations in the whole left frontotemporal network for phonological and syntactical processing as the most consistent finding.[2] Based on these imaging methods, progressive nonfluent aphasia can be regionally dissociated from the other subtypes of frontotemporal lobar degeneration, frontotemporal dementia and semantic dementia.

Classification

Some confusion exists in the terminology used by different neurologists. Mesulam's original description in 1982 of progressive language problems caused by neurodegenerative disease (which he called primary progressive aphasia (PPA) [3][4] included patients with progressive nonfluent (aphasia, semantic dementia, and logopenic progressive aphasia.[5][6][7]

Management

No cure or treatment for this condition has been found. Supportive management is helpful.

See also

• Alzheimer's disease
• Corticobasal degeneration
• Pick's disease

References

1. M. Hunter Manasco (2014). Introduction to Neurogenic Communication Disorders. pp. 86–88. ISBN 9780323290920.
2. Schroeter ML, Raczka KK, Neumann J, von Cramon DY (2007). "Towards a nosology for frontotemporal lobar degenerations – A meta-analysis involving 267 subjects". NeuroImage. 36 (3): 497–510. doi:10.1016/j.neuroimage.2007.03.024. PMID 17478101.
3. Mesulam M (1982). "Slowly progressive aphasia without generalized dementia". Ann. Neurol. 11 (6): 592–8. doi:10.1002/ana.410110607. PMID 7114808.
4. Mesulam MM (April 2001). "Primary progressive aphasia". Ann. Neurol. 49 (4): 425–32. doi:10.1002/ana.91. PMID 11310619.
5. Gorno-Tempini ML, Hillis AE, Weintraub S, et al. (March 2011). "Classification of primary progressive aphasia and its variants". Neurology. 76 (11): 1006–14. doi:10.1212/WNL.0b013e31821103e6. PMC 3059138. PMID 21325651.
6. Bonner MF, Ash S, Grossman M (November 2010). "The new classification of primary progressive aphasia into semantic, logopenic, or nonfluent/agrammatic variants". Curr Neurol Neurosci Rep. 10 (6): 484–90. doi:10.1007/s11910-010-0140-4. PMC 2963791. PMID 20809401.
7. Harciarek M, Kertesz A (September 2011). "Primary progressive aphasias and their contribution to the contemporary knowledge about the brain-language relationship". Neuropsychol Rev. 21 (3): 271–87. doi:10.1007/s11065-011-9175-9. PMC 3158975. PMID 21809067.

Further reading

• Gliebus G (March 2010). "Primary progressive aphasia: clinical, imaging, and neuropathological findings". Am J Alzheimers Dis Other Demen. 25 (2): 125–7. doi:10.1177/1533317509356691. PMID 20124255.
• Gorno-Tempini ML, Dronkers NF, Rankin KP, et al. (March 2004). "Cognition and anatomy in three variants of primary progressive aphasia". Ann. Neurol. 55 (3): 335–46. doi:10.1002/ana.10825. PMC 2362399. PMID 14991811.
• Henry ML, Gorno-Tempini ML (December 2010). "The logopenic variant of primary progressive aphasia". Curr. Opin. Neurol. 23 (6): 633–7. doi:10.1097/WCO.0b013e32833fb93e. PMC 3201824. PMID 20852419.
• Mesulam MM (October 2003). "Primary progressive aphasia—a language-based dementia". N. Engl. J. Med. 349 (16): 1535–42. doi:10.1056/NEJMra022435. PMID 14561797.
• Reilly J, Rodriguez AD, Lamy M, Neils-Strunjas J (2010). "Cognition, language, and clinical pathological features of non-Alzheimer's dementias: an overview". J Commun Disord. 43 (5): 438–52. doi:10.1016/j.jcomdis.2010.04.011. PMC 2922444. PMID 20493496.
• Rohrer JD, Knight WD, Warren JE, Fox NC, Rossor MN, Warren JD (January 2008). "Word-finding difficulty: a clinical analysis of the progressive aphasias". Brain. 131 (Pt 1): 8–38. doi:10.1093/brain/awm251. PMC 2373641. PMID 17947337.