Autonomic Neuropathy and Albuminocytologic Dissociation in Cerebrospinal Fluid As the Presenting Features of Primary Amyloidosis: A Case Report

Causes of albuminocytological dissociation and the impact of age-adjusted cerebrospinal fluid protein reference intervals: a retrospective chart review of 2627 samples collected at tertiary care centre

OBJECTIVE

We set out to test the discriminative power of an age-adjusted upper reference limit for cerebrospinal fluid total protein (CSF-TP) in identifying clinically relevant causes of albuminocytological dissociation (ACD).

METHODS

We reviewed the charts of 2627 patients who underwent a lumbar puncture at a tertiary care centre over a 20-year period. Samples with CSF-TP above 45 mg/dL (0.45 g/L) were included. Samples with white cell count >5×10⁹/L, red cell count >50×10⁹/L and glucose <2.5 mmol/L (45 mg/dL) were excluded as were samples with incomplete data and those taken from paediatric patients (ie, age <18 years old). Patients with CSF-TP elevated above 45 mg/dL were considered to have 'pseudo' ACD unless their CSF-TP was in excess of age-adjusted norms in which case they were considered to have 'true' ACD. Adjustment for sex was not applied to the age-adjusted norms although the importance of gender has been previously described.

RESULTS

The presence of ACD was associated with a broad range of neurological diagnoses. Among all 2627 patients with ACD, a clinical diagnosis explaining CSF-TP elevation was identified in 57% of cases. 'True' ACD was associated with a suitable diagnosis in 75% of cases, whereas patients with 'pseudo' ACD showed an appropriate diagnosis in only 51% of cases. Use of an age-adjusted upper reference limit favoured the detection of polyneuropathy patients (13.5% proportionate increase) and excluded a larger number of patients with isolated headache (10.7% proportionate decrease; p<0.0001).

CONCLUSIONS

Elevated CSF-TP is a common finding, with a range of underlying causes. Use of an age-adjusted upper reference limit for the CSF-TP value improves diagnostic specificity and helps to avoid overdiagnosis of ACD.

Incomplete intestinal obstruction as an initial and persistent presentation in chronic inflammatory demyelinating polyneuropathy: A case report

RATIONALE

Autonomic symptoms are not uncommon in chronic inflammatory demyelinating polyneuropathy (CIDP), but they are mostly mild and transient and are overshadowed by somatic manifestations. Here, we report a very unusual case of CIDP with severe autonomic symptom, intestinal obstruction, as initial and persistent symptom which responded well to high-dose glucocorticoid and intravenous immunoglobulin treatment.

PATIENT CONCERNS

We described a patient with CIDP with precedent and long-lasting incomplete intestinal obstruction. Clinical manifestations were precedent and chronic abdominal pain, distension and constipation, and later numbness and weakness of lower and upper limbs. Radiograph showed incomplete intestinal obstruction, cerebrospinal fluid (CSF) showed albuminocytological dissociation and electromyography indicated neurogenic lesion.

DIAGNOSES

CIDP with incomplete intestinal obstruction was diagnosed based on the history, related symptoms, typical abdominal radiograph, CSF albuminocytological dissociation, and electromyographic findings.

INTERVENTIONS

The patient was treated with intravenous methylprednisolone and immunoglobulin.

OUTCOMES

After treatment, the intestinal obstruction disappeared and the somato-symptoms improved greatly and gradually.

LESSONS

This case highlights the need for diagnostic vigilance in cases of incomplete intestinal obstruction of unknown cause. We recommend CSF and electromyography examination in view of rare but possibility of CIDP.