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Case Reports
. 2018 Jul 25:2018:bcr2018224412.
doi: 10.1136/bcr-2018-224412.

Avoiding diagnostic delay for mucopolysaccharidosis IIIB: do not overlook common clues such as wheezing and otitis media

Toshifumi Yodoshi  1   2 , Thomas L Hurt  3
Affiliations
Case Reports

Avoiding diagnostic delay for mucopolysaccharidosis IIIB: do not overlook common clues such as wheezing and otitis media

Toshifumi Yodoshi et al. BMJ Case Rep. .

Abstract

Mucopolysaccharidosis IIIB (MPS IIIB) is an autosomal recessive lysosomal storage disorder. In comparison to Hurler syndrome (MPS I) and Hunter syndrome (MPS II), characteristic facial and physical features tend to be milder and progression of neurological symptoms may initially be slower. Obvious neurological and behavioural symptoms may not appear until age 2-6 years, but once they begin, progression is relentless, leading to death by the early 20s. Although there is currently no known cure for MPS IIIB, enzyme replacement clinical trials are showing hope for delay in the progression of symptoms. Early diagnosis is therefore necessary before neurological symptoms have progressed. In our case, MPS IIIB was diagnosed at an early age because recurrent wheezing and otitis media in conjunction with hepatomegaly were recognised as more than trivial findings. A thorough examination and a definitive proactive decision to perform a liver biopsy resulted in early diagnosis of a rare disease.

Keywords: asthma; congenital disorders; genetics; liver disease; paediatrics.

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Conflict of interest statement

Competing interests: None declared.

Figures

Figure 1
Figure 1
Characteristic facial appearance, showing coarse face and hirsutism.
Figure 2
Figure 2
Extensive Mongolian spots on his back.
Figure 3
Figure 3
Lumber spine, lateral view, at 2 years of age, showing rounding of the vertebral bodies.
Figure 4
Figure 4
T2-weighted MRI shows enlarged lateral ventricles.
Figure 5
Figure 5
Stained Kupffer cells (arrowheads) and acid mucopolysaccharide in hepatocytes stained blue with colloidal iron stain (×200, colloidal iron staining).
Figure 6
Figure 6
Clear or lucent lysosomes with reticulo-particulate contents in a hepatocyte (×3000, electron micrograph).
Figure 7
Figure 7
A granular histiocyte (Buhot cell) present in the bone marrow (×1000, HE staining).
See this image and copyright information in PMC

References

    1. Sanfilippo SJ, Podosin R, Langer L, et al. . Mental retardation associated with acid mucopolysacchariduria (heparitin sulfate type). J Pediatr 1963;63:837–8. 10.1016/S0022-3476(63)80279-6 - DOI
    1. Valstar MJ, Ruijter GJ, van Diggelen OP, et al. . Sanfilippo syndrome: a mini-review. J Inherit Metab Dis 2008;31:240–52. 10.1007/s10545-008-0838-5 - DOI - PubMed
    1. Tanaka A, Kimura M, Lan HT, et al. . Molecular analysis of the alpha-N-acetylglucosaminidase gene in seven Japanese patients from six unrelated families with mucopolysaccharidosis IIIB (Sanfilippo type B), including two novel mutations. J Hum Genet 2002;47:484–7. 10.1007/s100380200070 - DOI - PubMed
    1. Chinen Y, Tohma T, Izumikawa Y, et al. . Sanfilippo type B syndrome: five patients with an R565P homozygous mutation in the alpha-N-acetylglucosaminidase gene from the Okinawa islands in Japan. J Hum Genet 2005;50:357–9. 10.1007/s10038-005-0258-4 - DOI - PubMed
    1. Chuang SC, Hwu WL, Wu CC, et al. . Diagnosis of mucopolysaccharidosis type IIIB. Zhonghua Min Guo Xiao Er Ke Yi Xue Hui Za Zhi 1996;37:320–3. - PubMed

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