Page 94 - The lraternational Journal of the Royal Society of Thailand.indd

The International Journal of the Royal Society of Thailand
Volume XV-2023

Nevertheless, DM patients often have coexisting diseases and are prone to have
other causes of neuropathy. Additional clinical information and investigations should
also be done for differential diagnosis such as medication side effects, uremia, vitamin
B12 deficiency, hypothyroidism, monoclonal gammopathy, etc. The initial laboratory
testing package should include complete blood count, thyroid function test, vitamin

B12 level, serum immunofixation electrophoresis and other routine blood chemistry
(England et al, 2009). Autonomic testing and other additional investigations may be
required in some cases (England et al, 2009).

In 2007 survey in Thailand, involving 1078 DM patients in primary care health
clinic, showed peripheral neuropathy prevalence of 34%. It is the most common

complication from DM and might explain the high rate of foot ulcers in this cohort
(Nitiyanant et al, 2007). Routine practice of regular assessment for potential complications
are not performed adequately. Among Asian countries, the prevalence is in the range

of 33-58 % depending on screening tools (Nitiyanant et al, 2007; Ferrario et al, 2013).
Finally, it leads to burden and cost to the society (Malik et al, 2009). Regrettably, it is
often underdiagnosed or misdiagnosed because of low awareness amongst both
patients and physicians. Furthermore, crude screening tools, such as the 10-g mono-
filament, can detect only for large fiber polyneuropathy and is often positive only in

severe neuropathy. Moreover, it is often normal is small fiber neuropathy which will
lead to false diagnosis.

Diagnosis and screening

The diagnosis of DSPN is quite straightforward. It requires a diabetic history,
neuropathy signs and symptoms, abnormal screening test and exclusion of other
causes of neuropathy. The Toronto consensus criteria can further define the level of
certainty of diagnosis to possible, probable and confirmed DSPN depending on the

evidence and confirmatory test. If possible, nerve conduction studies should be done
to characterize the type and severity of polyneuropathy. In research setting, quantitative
sensory testing and intra-epidermal nerve fiber density from skin biopsy are helpful

for objective measurement (Feldman et al, 2019; Ziegler et al, 2022; England et al, 2009;
ElSayed et al, 2023). Regarding the diagnosis of neuropathic pain, Thai neuropathic
pain guideline recommended Thai DN4 questionnaire (Thai version of Neuropathique
4 Questionnaire) for screening and diagnosis of neuropathic pain.

American Diabetic Association (ADA) recommended that all diabetic patients

should be assessed for DSPN starting diagnosis of type2 DM, 5 years after diagnosis
of type1 DM and at least annually thereafter. Screening patient with prediabetes who

86 Revisiting Diabetic Polyneuropathy and Autonomic Neuropathy