Endocrine Abstracts

46yr old gentleman. Recently diagnosed with late-onset type 1 diabetes.HBA1C of 12% (108 mmol/molHb) at diagnosis. Also Vit B12 deficient. Normal TSH, Normal 9am cortisol, Normal TTG antibodies. On Novomix 30 Insulin.

No diabetic end-organ complication. Smokes 8g tobacco/day. Moderate alcohol intake

Presented with a year history of painful neuropathy,started with his left toes and progressed in an ascending manner to involve the whole foot ant the lower leg. Shortly afterwards, his right leg became involved in exactly the same manner. At a later stage, both hands became involved spreading to the forearms.

Associated with these was marked wasting of his Quadriceps,calves, tricep and bicep muscles.

Neurological examination showed normal strength but quite significant wasting especially in both quadriceps. There were patchy areas of decreased sensation all over his body with impaired proprioception distally in his right leg. Lower limb reflexes were absent.

Rest of systems examination were normal.

Results: Polyneuropathy Screen -

Normal U & E, folate and ferritin levels

Normal FBC

TSH Normal

Purkinje Cell Antibodies NEGATIVE

Cryoglobulins Not detected

Serum ACE 45 (Ref: 8–70 U/L)

Myeloma screen - Negative

EMG - Evidence of mild neurogenic change in the right lower limb

Nerve Conduction Report - Reduced CMAP(compound muscle action potential) amplitude and conduction velocity compatible with a primarily demyelinating polyradiculoneuropathy - Likely CIDP

Treatment: Currently has had IV Immunoglobulin treatment with good response i.e marked improvement in muscle strength and pain

Discussion: CIDP is suspected in patients who develop a sub-acute and progressive predominantly motor neuropathy with proximal weakness, which is distinguished from the “typical” diabetic neuropathy that is predominantly sensory and length-dependent. Incidence of diabetes in CIDP and vice versa may be higher than in the general population. Diagnostic criteria for CIDP in diabetes is similar to CIDP in general. However, making a diagnosis of CIDP in diabetics can be rather difficult as nerve conduction abnormalities are common in diabetes along with axon loss and demyelination. This distinction is of importance, as these patients can respond to immune therapies similar to patients with CIDP without diabetes

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.