Consensus Guidelines for the Management of
Insulin-Dependent (Type 1) Diabetes — Chapter 4
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4.0 KIDNEY, EYE AND NERVE DISEASE, AND FOOT PROBLEMS
IDDM CONSENSUS GUIDELINES Chapter 4 LATE COMPLICATIONS: Kidney
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4.1 Kidney disease (nephropathy) and hypertension
- Diabetic nephropathy is a major cause of morbidity and mortality among patients with IDDM.
- Albuminuria is a strong predictor, particularly of cardiovascular mortality.
- The development and progression of diabetic nephropathy depends on metabolic control, hypertension, and the genetic background. Thus strict metabolic and blood pressure control is associated with an improved prognosis.
- Hypertension in IDDM is usually associated with renal disease, appearing at the time of microalbuminuria.
- These patients are at high risk of ischaemic heart disease and retinopathy, and often have a dyslipidaemia ( lipids/IDH ).
4.1.1 Screening and diagnosis
Microalbuminuria (urinary albumin excretion 30-300 mg/24-h or 20-200 µg/min) is the earliest detectable manifestation of renal disease, and a predictor of all types of late tissue damage from diabetes.
- All patients with IDDM should be screened yearly for microalbuminuria after onset of puberty using albumin/creatinine ratio or spot albumin concentration. Confirmation of disease if >2.5 mg/mmol or >20 mg/l is by timed collection.
- Reagent strip positive albuminuria should be checked for at each consultation.
- Proteinuria with short diabetes duration or absence of retinopathy may indicate non-diabetic renal disease and is an indication for renal biopsy.
4.1.2 Management of hypertension/microalbuminuria
By vigorous treatment of hypertension the rate of loss of renal function can be significantly reduced. The target for supine blood pressure should be a strict 140/85 mmHg, or lower in the younger patient.
- Non-pharmacological treatment includes cessation of smoking, reduced salt intake, and reduced protein intake as first line measures ( diet ).
- The choice of drug therapy is made from the main groups of antihypertensive agents, with caution over drugs disturbing lipid metabolism and affecting the adrenergic counter-regulatory response to hypoglycaemia (Þ-adrenergic blockers and thiazides in particular).
- Good blood glucose control (HbA1c, normal mean +3-5SD) may still reduce the progression of nephron loss at this stage ( metabolic targets ).
4.1.3 Other management of renal disease
- The principles of management of diabetic nephropathy are as for other renal disease.
- However earlier evaluation by a nephrologist (at creatinine 200-300 µmol/l), and earlier renal support therapy, are desirable.
- Renal transplantation is the preferred treatment for end stage renal failure. CAPD has proven particularly successful in diabetic patients.
No patient should be excluded from renal replacement
programmes solely on the basis of having diabetes.
IDDM CONSENSUS GUIDELINES Chapter 4 LATE COMPLICATIONS: Kidney
IDDM CONSENSUS GUIDELINES Chapter 4 LATE COMPLICATIONS: Eye
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4.2 Eye Disease and Retinopathy
- Diabetic eye disease is a leading cause of visual loss in the working population.
- With good metabolic control sight-threatening retinopathy is preventable ( metabolic targets ).
- Surveillance can detect high risk lesions, and 90 % of blindness then prevented by photocoagulation.
4.2.1 Diagnosis and screening
Surveillance is not a complete clinical assessment but a means of identifying patients at risk. Recall and record systems should ensure it occurs regularly.
- Surveillance involves:
- Fundal examination by ophthalmoscopy / retinal photography after dilation of pupils;
- Annual measurement of visual acuity (glasses or pinhole);
- Assessment of visual symptoms, hypertension, and smoking.
- Ophthalmoscopy is sensitive and specific when performed by well trained observers but does not produce objective permanent documentation.
- Retinal photography through dilated pupils can provide a permanent record.
- The purpose of retinal surveillance is to determine those patients requiring expert intervention. Non-proliferative retinopathy may not require referral. Macular involvement, pre-proliferative change, or proliferative change require immediate specialist assessment.
- Eyes should be examined at the onset of puberty and annually thereafter (2 yearly if by an ophthalmologist).
- Non-sight threatening retinopathy should be reviewed every 3-12 months.
- A need for more frequent examination is suggested by hypertension, microalbuminuria, and pregnancy.
The primary management of diabetic eye disease
is by careful attention to the metabolic control
targets from the time of diagnosis.
4.2.2 Management of diabetic eye disease
- Eye care requires co-operation between the responsible physician and the ophthalmologist. The physician should co-ordinate care, taking responsibility for the medical treatment.
- Close attention to metabolic control is required.
- Strict anti-hypertensive control is recommended ( blood pressure ).
- Timely intervention with photocoagulation can usually prevent loss of vision.
- Attention should be paid to the psychological, social, and financial aspects of visual impairment where it develops.
IDDM CONSENSUS GUIDELINES Chapter 4 LATE COMPLICATIONS: Eye
IDDM CONSENSUS GUIDELINES Chapter 4 LATE COMPLICATIONS: Foot
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4.3 Foot Problems of Diabetic Patient
Foot ulceration, and thus amputation,
is nearly always preventable.
- Foot problems can pose a major threat to patient with long-term diabetes.
- Neuropathic ulceration and subsequent amputation are the greatest problem in IDDM, and are almost entirely preventable ( neuropathy ).
- Vascular (and mixed) ulceration also occur, especially in those with diabetic renal disease.
- Foot problems are thus a major cause of morbidity, and a major health-care cost.
The patients with highest risk of serious foot problems are those with:
- a history of foot ulceration (or contralateral amputation)
- symptoms and/or signs of neuropathy or ischaemic vascular disease
- other long-term complications
- poor metabolic control / poor hygiene / poor diabetes education
- foot deformities / poor footwear
- severe visual impairment
4.3.1 Foot management guidelines
Diabetes care services should be structured to offer:
- Primary prevention through ( good metabolic control );
- Detection of patients with foot risk factors - regular surveillance;
- Risk factor management
- Salvage treatment
4.3.1.1 Surveillance
- Should be performed annually or more often if risk factors detected.
- Involves foot inspection for:
- ulceration, deformity, skin and nail condition, and ischaemia;
- assessment of claudication symptoms and peripheral pulses;
- assessment of vibration and 'pin prick' sensation;
- inspection of footwear;
- review of self-care behaviour.
4.3.1.2 Management
- Primary management once risk factors are found is by repeated education. Patients should be given a list of 'the commandments of foot-care' and explanation of their purpose.
- The assistance of a podiatrist (chiropodist) is important.
- Good footwear can be critical in the care of the neuropathic foot.
- Special footwear can be limb-saving in the face of foot deformities.
- Vascular surgery or angioplasty should be undertaken early for peripheral vascular disease.
- Stop smoking.
4.3.1.3 Established foot ulceration/infection
A treatment strategy should be available, and be able to rely on the co-ordinated efforts of a foot team consisting of diabetologist, podiatrist (chiropodist), orthotist, microbiologist, investigative radiologist, and vascular and orthopaedic surgeon.
- Aggressive, early, and continuing antibiotic therapy can be effective when evidence of deep infection or cellulitis is present.
- Local measures such as debridement should be employed.
- Plantar supportive casts facilitate the healing of neuropathic ulceration.
- Arterial surgery and removal of infected bone may be helpful.
- If amputation does become necessary, education of the use of the prosthesis is important, together with special attention to the remaining foot which is subject to new stresses.
IDDM CONSENSUS GUIDELINES Chapter 4 LATE COMPLICATIONS: Foot
IDDM CONSENSUS GUIDELINES Chapter 4 LATE COMPLICATIONS: Nerves
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4.4 Diabetic Nerve Damage
- Diabetic neuropathy (somatic and autonomic) is common and underdiagnosed.
- Nerve damage may be responsible for a variety of troublesome problems including painful neuropathy, foot ulceration, erectile impotence, gastroparesis, and abnormalities of sweating.
- With good metabolic control diabetic nerve damage is preventable
4.4.1 Diagnosis and screening
- Surveillance includes annual testing of vibration and 'pin prick' sensation.
- Annual review should also be the occasion for direct enquiry for symptoms of painful neuropathy and erectile impotence.
- Other manifestations of autonomic neuropathy should be sought in those with other late complications of diabetes, with blood glucose control problems, or if a procedure requiring anaesthesia is contemplated.
4.4.2 Management of diabetic nerve damage
- Prevention is by good metabolic control; no other means including drug therapy have as yet been shown to be beneficial. The practice of improving metabolic control after troublesome neuropathy has developed is of limited utility.
- Good foot care can prevent ulceration and amputation (see above).
- Painful neuropathy is a distressing and depressing condition; special counselling is required if it appears after tightening of blood glucose control. If there is inadequate response to simple analgesia and simple measures such as bed cradles, therapeutic trials are indicated of tricyclic agents (eg amitriptyline), high dose carbamazepine (600-1200 mg/day), and then phenytoin.
- Erectile impotence is common in middle aged men. Referral should be offered to a specialist service offering diagnostic investigations and appropriate pharmacological, psychological, or vascular treatment.
- Diabetic gastroparesis causes erratic blood glucose control and troublesome hypoglycaemia before other symptoms. Agents promoting gastric emptying (metaclopramide, domperidone, cisapride) are the only drugs with any proven effect.
- Diabetic nocturnal diarrhoea can be very distressing. High dose opiate derivatives (codeine, loperamide, diphenoxylate) may help.
- Gustatory and other disorders of sweating may respond to topical or oral anticholinergic agents.
IDDM CONSENSUS GUIDELINES Chapter 4 LATE COMPLICATIONS: Nerves
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