LF_HAND_003
Immunology Laboratory
Gartnavel General Hospital, Glasgow
User Manual
Page 1 of 18
Copyholder Reporting Room
IMMUNOPATHOLOGY LABORATORY HANDBOOK
Contents
INTRODUCTION .......................................................................................................................................... 3
CONTACT DETAILS.................................................................................................................................... 3
Head of Department ............................................................................................................................... 3
Laboratory Manager ............................................................................................................................... 3
Departmental Secretaries ........................................................................................................................ 3
Laboratory Enquiries .............................................................................................................................. 3
Postal Address ........................................................................................................................................ 3
Normal Laboratory Working Hours ....................................................................................................... 3
CLINICAL IMMUNOLOGY SERVICES..................................................................................................... 4
Immunodeficiency Clinics .......................................................................................................................... 4
Allergy Clinics ........................................................................................................................................... 4
SAMPLES / REQUESTS / RESULTS .......................................................................................................... 5
Sample Identification Requirements ....................................................................................................... 5
High Risk Samples ................................................................................................................................. 5
Urgent Samples ...................................................................................................................................... 5
Electronic Requesting of Immunology Tests.......................................................................................... 5
Reports and Results ................................................................................................................................ 5
SAMPLE BOTTLES & VOLUMES ............................................................................................................. 6
IMMUNOLOGY TESTS ............................................................................................................................... 7
Allergy / Hypersensitivity Tests ................................................................................................................. 7
Autoantibodies............................................................................................................................................ 8
Complement ..............................................................................................................................................13
Immunochemistry ......................................................................................................................................14
Cellular Studies .........................................................................................................................................17
GUIDE TO APPROPRIATE INVESTIGATIONS .......................................................................................18
Page 2 of 18
INTRODUCTION
The Immunology Department comprises both Clinical and Laboratory Services. The
Immunology Laboratory is based at the Gartnavel General Hospital. During routine
hours a member of the medical staff is always available for consultation and we are
happy to answer enquiries about the use & interpretation of test results. Outside these
times a member of staff may be contacted through the hospital switchboard for the
discussion of urgent clinical cases.
CONTACT DETAILS
Head of Department
Dr M J Thomas
0141 301 7753 or 57753
Laboratory Manager
Mr E Galloway
0141 301 7747 or 57747
Departmental Secretaries
Telephone
0141 301 7753/7754 or ext 57753/57754
Fax
0141 301 7750
Laboratory Enquiries
0141 301 7752 or 57752
Postal Address
Department of Immunology
1st Floor, Laboratories Building
Gartnavel General Hospital
21 Shelley Road
Glasgow
G12 0XL
Normal Laboratory Working Hours
0850 to 1650 Monday to Friday
Page 3 of 18
CLINICAL IMMUNOLOGY SERVICES
Immunodeficiency Clinics
A comprehensive service is provided for the investigation and management of adults with
(suspected) Primary Immunodeficiency (includes Hereditary Angioedema/C1 inhibitor
deficiency).Outpatient clinics are held at Gartnavel General Hospital. Day case facilities
are available at Gartnavel General Hospital for patients requiring regular immunoglobulin
replacement therapy and a Home Therapy Programme is in place. Paediatric
Immunodeficiency services are based at Yorkhill.
Allergy Clinics
Allergy clinics are held mainly at the Victoria Infirmary, Glasgow. These are intended
primarily for investigation and management of patients with anaphylaxis, food allergy
(rather than intolerance) and angioedema. Paediatric Allergy services are based at
Yorkhill.
Page 4 of 18
SAMPLES / REQUESTS / RESULTS
We cannot process samples unless we can be sure about the patient’s identity, the test(s)
required and where to send the result. Inadequately labelled samples will be discarded
and those accompanied by incomplete forms will not be processed.
Sample Identification Requirements
SAMPLES MUST HAVE
 patient’s full name (or proper coded identifier)
 date of birth and/or hospital or CHI number
 date and time of sample are essential for anaesthetic reactions, other serial
samples.
REQUEST FORMS MUST HAVE
 patient’s full name (or proper coded identifier)
 date of birth AND CHI number (if CHI unavailable, hospital number or patient’s
address)
 destination for report
 name of patient’s consultant or GP
 tests required
 date and time of sample are essential for anaesthetic reactions, cellular and
complement tests
DESIRABLE
 relevant clinical information
 name and contact/bleep number of requesting clinician
High Risk Samples
These include samples from patients known or thought likely to have infectious diseases
eg Hepatitis B or C, HIV infection, Creutzfeldt-Jacob disease and those to whom
radioactive materials have been administered therapeutically (not for investigation). The
nature of the hazard should be indicated and both the form and specimen(s) must be
marked with the yellow ‘Danger of Infection’ labels.
Urgent Samples
Contact laboratory to arrange urgent tests – writing ‘urgent’ on the form is insufficient.
Electronic Requesting of Immunology Tests
Immunology tests can be requested via the Order Comms system within the North
Glasgow Trust. Please contact IT if you do not already have access to this system. See
appendix for list of codes.
Reports and Results
Results are sent out by internal or royal mail. Results are also available in the electronic
blood sciences database accessible via North Glasgow ward terminals and networked
PCs. Please contact IT if you do not already have this facility.
Page 5 of 18
SAMPLE BOTTLES & VOLUMES
Autoantibodies / Coeliac Serology / Immunoglobulins / Paraproteins / C3&C4 / IgE
5-10mls sample of clotted, gel activated, blood (yellow top)
Anaesthetic reactions
Series of 3 timed samples of 5-10mls sample of clotted, gel activated, blood (yellow top)
sent at ~30mins, 1-3 hrs and ~24hrs after onset of reaction. Either send directly to
Immunology lab, or to local Biochemistry lab to be separated, frozen and forwarded to
Immunology on the next working day. Proforma request form available.
Bence Jones Protein / Urinary Free Light chains
20mls urine in preservative free container
Complement
AP100/CH100 – 5mls clotted blood (red top) to reach laboratory on day of venepuncture.
C1 inhibitor (functional) – 4 mls EDTA (purple top) to reach lab on day of venepuncture.
C1 inhibitor (quantitative) – 5-10mls sample of clotted, gel activated, blood (yellow top)
C3 & C4 – 5-10mls sample of clotted, gel activated, blood (yellow top)
Cryoglobulins (phone 57752 or 57758 to arrange)
10-20mls warm clotted blood (red top) in a flask of warm water.
Lymphocyte subsets
4mls EDTA blood (purple top) to reach laboratory within 20 hours & before 3pm on
Fridays. Do not refrigerate samples.
Lymphocyte function (phone 52327 to arrange)
5-7mls lithium heparin (green top) from both patient AND a healthy control to reach
laboratory before 3.30pm on day of venepuncture except Wednesdays & before 3pm on
Fridays. Samples cannot be processed on Wednesdays. Do not refrigerate samples.
Samples arriving without controls will not be analysed.
Neutrophil function (phone 52327 to arrange)
4mls EDTA (purple top) from both patient AND a healthy control
Sample to reach laboratory before 3.30pm on day of venepuncture & before 3pm on
Fridays.Do not refrigerate samples. Samples without controls will not be analysed.
Tryptase
5-10mls sample of clotted, gel activated, blood (yellow top)
Anaesthetic reactions – see above
Post mortem samples – blood from a peripheral vein is preferred.
Page 6 of 18
IMMUNOLOGY TESTS
Information, indications, interpretation of individual tests. Tests marked * are sent away.
Allergy / Hypersensitivity Tests
IgE – TOTAL
Quantitation of IgE is of value in some allergic and parasitic conditions and some rare
immunodeficiencies. A normal IgE level does not exclude significant allergic disease e.g.
food or latex allergy.
ALLERGEN SPECIFIC IgE (previously called ‘RAST’)
Sample - clotted blood – 3mls of blood usually sufficient for 6-7 allergens
IgE abs to a wide variety of allergens can be tested (see appendix)- it is essential to
indicate which ones are required on the basis of the history (symptoms typically occur
within an hour of exposure). Positive results indicate sensitisation to that allergen, but not
necessarily clinically significant allergy. Sensitivity varies widely depending upon the
allergen; therefore negative results do not necessarily exclude significant allergy. Results
should always be interpreted in the context of the clinical history.
ANAESTHETIC REACTIONS (also for other drug / allergic reactions)
Request form – proforma available
Samples - 3 clotted samples at ~30 minutes, 1-3 hours, ~24 hours after onset of reaction
Note; resuscitation ALWAYS takes priority over collection of samples.
Reactions may be caused by a range of agents including anaesthetic drugs, other drugs
(e.g. antibiotics, premed), plasma expanders, chlorhexidine or latex allergy and may
involve a variety of mechanisms. Details of the nature of the reaction and drugs given
should be given – suggest use proforma request form. Mast cell tryptase, complement and
IgE to latex & ethylene oxide will be measured in all patients. IgE to penicillin,
ampicillin, amoxycillin or suxamethonium will not be done routinely but should be
requested in patients exposed to these agents. Results do not affect the immediate
management. Close liaison with the laboratory is advised in the interpretation of results.
Additionally, West of Scotland patients may be referred to the Anaphylaxis Clinic based
at the Western Infirmary for further assessment / skin testing. UK guidelines produced by
AAGBI & BSACI are available at www.aagbi.org/pdf/Anaphylaxis.pdf
ASPERGILLUS IgG ANTIBODIES / PRECIPITINS
Sample – clotted blood
Associated with Allergic Broncho-Pulmonary Aspergillosis and aspergilloma. May also
be of use in assessing aspergillus colonisation in Cystic Fibrosis.
AVIAN PRECIPITINS - IgG to Pigeon
Sample – clotted blood
Positive levels indicate exposure to pigeon antigens and may be associated with Pigeon
Fancier’s Lung. High levels may be found in severe acute disease.
Page 7 of 18
FARMER’S LUNG SEROLOGY - IgG to M. FAENI
Sample – clotted blood
Positive levels indicate exposure to the fungus M. Faeni and may be associated with
Farmer’s Lung. High levels may be found in severe acute disease.
TRYPTASE
See also ‘Anaesthetic Reactions’
Tryptase levels are often but not always raised following anaphylactic reactions to drugs
or insect venom but less often in anaphylactoid reactions or in anaphylaxis triggered by
foods. A series of samples is recommended to minimise the chance of missing the peak
which is typically 1-3 hours after the onset of the reaction. Post mortem samples can be
assayed for tryptase - samples from peripheral veins are preferred (tryptase may be high
in intracardiac samples after CPR/trauma).
Tryptase may also be raised in mastocytosis.
Autoantibodies
ANA
See under Nuclear Antibodies
ANCA
See under Neutrophil Cytoplasmic Antibodies
ADRENAL ANTIBODIES
Sample – clotted blood
Positive in 60-70% of patients with idiopathic Addison’s disease. Adrenal antibodies may
be detectable prior the development of adrenal failure. They may also be found and in
cases of autoimmune ovarian failure.
*
C1q ANTIBODIES
Sample – clotted blood
May be found in patients with Hypocomplementaemic Urticarial Vasculitis (C3 & C4
levels very low). Also found in Lupus Nephritis but is not yet recommended for routine
monitoring / diagnostic purposes (suggest request C3 &C4 and dsDNA abs instead).
*
C3 NEPHRITIC FACTOR
Sample – clotted blood
This is an autoantibody associated with membranoproliferative glomerulonephritis and
partial lipodystrophy. C3 levels are invariably reduced in the presence of C3 nephritic
factor, therefore C3 levels should be measured first. See also complement section.
*
CARDIAC MUSCLE ANTIBODIES
Sample – clotted blood
Occur in some patients with Dressler’s syndrome or Post-cardiotomy syndrome.
Page 8 of 18
CARDIOLIPIN ANTIBODIES
Sample – clotted blood
Found in the Anti-Phospholipid Syndrome (APS). This is an acquired (not inherited)
disorder, the clinical features of which are: recurrent spontaneous abortion, recurrent
thromboses (arterial or venous) and thrombocytopaenia and laboratory features - either
lupus anticoagulant or medium or high titre cardiolipin abs on at least two occasions at
least 6 weeks apart. APS may occur as a primary syndrome or secondary to SLE. Weak
or transiently positive cardiolipin abs may occur secondary to infection, drugs and
neoplasia. Patients suspected of having APS should also be tested for lupus anticoagulant
(send sample to Haematology; see handbook for details).
CENTROMERE ANTIBODIES (included in ANA screen)
Sample – clotted blood
Indicated in the investigation of Raynaud’s phenomenon. Positive in 60-70% of patients
with the CREST variant of scleroderma and 20% of patients with systemic sclerosis.
Centromere abs are detected on the standard ANA screen ie ‘ANA negative’ means that
centromere abs are also negative.
COELIAC SEROLOGY
Sample – clotted blood
IgA Tissue Transglutaminase (TTG) abs are now the first line screening test for Coeliac
Disease. TTG is the antigen recognised by Endomysial abs. Specificity and sensitivity
for TTG abs are reported as >95% in untreated Coeliac Disease. Therefore a negative
result makes Coeliac disease very unlikely although does not completely exclude it. An
individual with Coeliac disease may have negative serology if they are IgA deficient or
on a gluten free diet. IgA endomysial abs are retained as a confirmatory test for TTG
positive samples; IgG endomysial abs may be detected in some IgA deficient individuals
with Coeliac disease. Gliadin and reticulin abs are no longer used because of poor
sensitivity / specificity. Patients with Dermatitis Herpetiformis may also have positive
coeliac serology.
dsDNA ANTIBODIES
Sample – clotted blood
Assayed routinely on any patient found to have an ANA > 1:160 (homogeneous pattern).
Their presence is strongly suggestive of SLE although they are present in only 40-60% of
patients with this disease. Positive DNA abs are very rarely found in the absence of a
positive ANA. Therefore ANA is recommended as the initial screening test and DNA abs
only recommended for monitoring patients with SLE/related disorders.
EXTRACTABLE NUCLEAR ANTIGENS (ENA) ANTIBODIES
Sample – clotted blood
Includes abs to Ro, La, Sm, RNP, Jo-1, CENPB and Scl-70
ENA abs aid the classification of connective tissue disease and provide prognostic
information. Their presence is strongly suggestive of an underlying CT disease, although
they are only present in a subset of such patients. ENA abs are assayed routinely on any
new patient with an ANA 1:160 (speckled or nucleolar pattern). ENA antibodies are not
Page 9 of 18
useful for monitoring disease activity. Positive ENA abs (including Ro) are very rarely
found in the absence of a positive ANA. Therefore ANA is recommended as the initial
screening test; ENA abs should only be requested in selected patients if there is a very
strong suspicion of connective tissue disease.
ENA
Ro
Disease Association
SLE (particularly photosensitivity)
Cutaneous lupus
Sjogren’s syndrome
Recurrent miscarriage
Neonatal lupus and congenital heart block
La
SLE
Sjogren’s syndrome
SLE.
SLE
Mixed Connective Tissue Disease.
Systemic Sclerosis (generalised scleroderma)
Scleroderma – CREST syndrome
Polymyositis or dermatomyositis especially
with respiratory involvement
Sm
RNP
Scl-70
CENPB
Jo-1
ENDOMYSIAL IgA & IgG ANTIBODIES
See under Coeliac Serology. Endomysial abs have been replaced by Tissue
Transglutaminase abs as the first line test for Coeliac Disease.
GASTRIC PARIETAL CELL ANTIBODIES
Sample – clotted blood
Occur in 95% of patients with Pernicious Anaemia and may be detectable prior to the
development of clinically apparent disease. They also occur in up to 15% of the normal
population, the incidence rising with increasing age.
GLIADIN ANTIBODIES
See under Coeliac serology
GLOMERULAR BASEMENT MEMBRANE (ANTI-GBM) ANTIBODIES
Sample – clotted blood
Positive in Goodpasture’s syndrome.
*
ANTI-IgA ANTIBODIES
Sample – clotted blood
May be associated with reactions to blood products in IgA deficient patients. Appropriate
notification of patients / other clinicians / Blood Bank is advised.
Page 10 of 18
*
INTRINSIC FACTOR ANTIBODIES
Sample – clotted blood
Positive in up to 50% of patients with Pernicious Anaemia. Intrinsic Factor abs are very
specific for Pernicious Anaemia. Samples are sent to Monklands District General.
*
ISLET CELL ANTIBODIES
Sample – clotted blood
Found in newly diagnosed IDDM. May also be present prior to the development of
clinical symptoms. Positive islet cell abs in patients with apparent NIDDM, gestational
diabetes or in relatives of IDDM patients indicate increased risk of developing IDDM.
LIVER KIDNEY MICROSOMAL (LKM) ANTIBODIES
Sample – clotted blood
Found in a sub-group of patients with autoimmune hepatitis and is associated with a
particularly aggressive form of the disease especially in children.
MITOCHONDRIAL ANTIBODIES
Sample – clotted blood
High titres occur in 95% of patients with Primary Biliary Cirrhosis and may be detectable
prior to the development of abnormal liver function. Low titres may also be found in
Chronic Active Hepatitis. Unless specified, only M2 pattern mitochondrial abs are
reported.
NUCLEAR ANTIBODIES (ANA)
Sample – clotted blood
Indicated in the investigation of suspected connective tissue disease and autoimmune
liver disease. They are present in elevated titres (>160) in 95% of untreated cases of
SLE; their absence makes SLE very unlikely. ANAs also occur in a number of other
conditions eg Juvenile Chronic Arthritis, Sjogren’s syndrome, Fibrosing Alveolitis,
Autoimmune Hepatitis, autoimmune thyroid disease, viral infections (EBV, CMV) and in
drug reactions. The frequency of low titre ANA in normal individuals rises with
increasing age. ENA and dsDNA abs will be requested automatically on all samples
found to have positive ANAs of a relevant pattern and titre. Centromere abs are
detectable on the ANA screen and do not need to be requested separately.
Page 11 of 18
NEUTROPHIL CYTOPLASMIC ANTIBODIES – ANCA
Sample – clotted blood
Indicated in the investigation of vasculitis. There are three main patterns – C-ANCA, PANCA and atypical ANCA. These patterns relate to different antigenic specificities eg
proteinase 3 (PR3), myeloperoxidase (MPO) and others. All positive ANCAs are tested
for reactivity against PR3 and MPO.
Pattern
C-ANCA
Antigen
PR3
Disease Association
Wegener’s granulomatosus
P-ANCA
MPO
Systemic vasculitis eg
Microscopic Polyangiitis
Churg Strauss,
Crescentic glomerulonephritis
Atypical ANCA
various
Wide range of inflammatory,infective & neoplastic diseases but the
clinical utility of atypical ANCAs has not yet been established.
NB - all types of ANCA have been reported in a wide range of other conditions e.g.
infection, neoplasia and inflammatory disease as well as vasculitis
*
OVARIAN ANTIBODIES
Sample – clotted blood
May be found in premature ovarian failure. Samples are tested on adrenal tissue first.
Those giving negative results are considered to have no detectable ovarian antibodies.
Samples giving positive results are sent away for further testing.
PHOSPHOLIPID ANTIBODIES
See under Cardiolipin antibodies
RHEUMATOID FACTOR
Sample – clotted blood
Used in the investigation of inflammatory arthropathies to differentiate sero-negative
from sero-positive arthritides. In Rheumatoid Arthritis, high titres may be associated
with extra-articular manifestations e.g. vasculitis and nodules. RFs are not of value in
monitoring disease activity. RFs may occur in other connective tissue/autoimmune
diseases, cryoglobulinaemia (may be very high titre), infections and in some healthy
individuals (often low titre). Absence of Rheumatoid Factor does NOT exclude
Rheumatoid Arthritis.
*
SKELETAL MUSCLE ANTIBODIES
Sample – clotted blood
Skeletal muscle antibodies are characteristically associated with thymoma and
myasthenia gravis but also occur in some patients with hepatitis, acute viral infections
and polymyositis.
Page 12 of 18
SKIN REACTIVE ANTIBODIES
Sample – clotted blood
Two varieties are recognised:
Intercellular substance abs - found in Pemphigus
Basement zone abs - found in Bullous Pemphigoid and occasionally Epidermolysis
Bullosa Acquista.
SMOOTH MUSCLE ANTIBODIES
Sample – clotted blood
Found in Autoimmune Hepatitis, often in association with positive ANA and
occasionally mitochondrial abs. May also occur in other settings eg viral infections
especially EBV and Hepatitis A. Only actin pattern smooth muscle abs are reported.
THYROID ANTIBODIES
Now measured in biochemistry
Thyroid peroxidase (TPO) antibodies (previously called thyroid microsomal antibodies)
are found in Primary Myxoedema, Hashimoto’s thyroiditis and Graves’ disease. In the
absence of thyroid disease, positive thyroid peroxidase antibodies may be predictive of
future thyroid disease and regular follow-up of clinical and biochemical parameters is
advised. TSH receptor antibodies are found in Graves’ disease but are difficult to
measure and rarely required to establish the diagnosis.
TISSUE TRANSGLUTAMINASE IgA ABS
See under Coeliac Serology.
Complement
ALTERNATE PATH COMPLEMENT - AP100
Sample - 5mls clotted blood (red top) to reach laboratory on day of venepuncture.
Measures the integrity of the alternate and terminal complement pathways. Rare inherited
deficiencies in these pathways predispose to neisserial infections. Indicated in the
investigation of patients with recurrent/atypical meningococcal infection or a family
history of neisserial infection.
CLASSICAL PATH COMPLEMENT - CH100
Sample - 5mls clotted blood (red top) to reach laboratory on day of venepuncture.
Measures the integrity of the classical and terminal complement pathways. Rare inherited
deficiencies in these pathways predispose to sepsis, immune complex disease and
neisserial infection. Indicated in the investigation of patients with recurrent pyogenic
infections, recurrent/atypical meningococcal infection, atypical immune complex
disorders or a family history of these.
C1 INHIBITOR
Sample for quantitative assay – clotted blood; request C3 & C4 on same sample
Sample for functional assay - 4 mls EDTA to reach lab on day of venepuncture
Page 13 of 18
Low levels of C1 inhibitor are found in 85% of patients with Hereditary Angioedema.
The remaining 15% have normal levels but a non-functional molecule. Urticaria is not a
feature of this condition. There is a rarer acquired form which may be associated with
lymphoproliferative disorders or SLE. In all forms of deficiency, C4 levels are very low
during attacks and often between attacks; therefore a normal C4 level essentially excludes
all forms of C1 inhibitor deficiency.
*
C1q
Sample – clotted blood
Only indicated for the differentiation of hereditary vs. acquired C1inhibitor deficiency.
Note this test measures C1q and NOT anti-C1q antibodies.
C3 and C4
Sample – clotted blood
Useful in the investigation / monitoring of patients with connective tissue disease/other
inflammatory disorders. Serial measurements are more useful than single point levels.
C3
High
C4
High
Low
Low
Low
Normal
Normal Low
Association
Acute phase reactions
Immune complex mediated disease eg SLE
Sepsis
Haemdilution
Liver disease
Hypcomplementaemic urticarial vasculitis
Gram negative septicaemia
Post-streptococcal nephritis
Membranoproliferative glomerulonephritis
C3 nephritic factor
Inherited deficiency of C3, Factor H or I (rare)
C1 inhibitor deficiency
Cryoglobulinaemia
Inherited deficiency of C4 null alleles (common in SLE)
C3 NEPHRITIC FACTOR
See under autoantibodies
Immunochemistry
BENCE-JONES PROTEIN / URINARY FREE LIGHT CHAINS
A urine sample should accompany ALL serum samples in cases of suspected myeloma
since up to 20% of myeloma patients have no detectable paraprotein in the serum.
CRYOGLOBULINS
Sample - 10-20mls warm clotted blood (red top) in a flask of warm water.
Page 14 of 18
Cryoglobulin studies are indicated in the investigation of patients with features of
hyperviscosity, Raynaud’s or unexplained vasculitis. A warm separated sample is
required. GPs should refer patients to hospital for the appropriate collection of samples.
For in-patients, blood should be taken into a pre-warmed syringe / vacutainer and
transported to the immunology laboratory in a thermos flask containing water at 37C.
Flasks can be obtained by contacting the Department. All detectable cryoglobulins are
typed.
FUNCTIONAL (SPECIFIC) ANTIBODIES
Sample – clotted blood
These comprise abs to tetanus, pneumococci and Hib and are indicated as part of the
investigation of suspected immune deficiency.
IgD
Sample – clotted blood
This is only of value in the assessment of rare periodic fever syndromes.
IgG SUBCLASSES
These have largely been replaced by Functional antibodies which provide a better
indicator of humoral immunity.
IMMUNOGLOBULINS - IgA, IgA, IgM & serum electrophoresis
Sample – clotted blood
Useful in the investigation of suspected immunodeficiency and lymphoproliferative
diseases. Polyclonal elevations may occur in a variety of disorders including chronic
infectious/inflammatory conditions and liver disease. If a paraprotein is detected, it will
automatically be typed and quantified. In patients known to have paraproteins, request
IGS to monitor paraprotein level and send urine for BJP.
PARAPROTEINS
See also under Immunoglobulins
Malignant Paraproteins — are usually of high concentration, associated with low levels
of the non-paraprotein immunoglobulins (immunoparesis) and with the presence of free
monoclonal light chains in the urine (Bence-Jones Protein). Most often occur in multiple
myeloma but may also be seen in other lymphoproliferative diseases e.g. Waldenstrom’s
Macroglobulinaemia, CLL and NHL.
Monoclonal gammopathy of undetermined significance (MGUS) – these are paraproteins
found in patients without an identifiable underlying disease. The paraprotein is usually
small and not accompanied by immunoparesis or free urinary light chains (BJP). MGUS
may be caused by the same group of conditions which cause a polyclonal increase in
immunoglobulins. MGUS may ultimately undergo malignant transformation (1-2% per
annum) and long term monitoring is advised.
Page 15 of 18
SERUM FREE LIGHT CHAINS
Sample – clotted blood
Indicated for the investigation of suspected light chain myeloma or AL amyloid.
Typically either kappa OR lambda light chains are raised in these disorders and the
kappa/lambda ratio is abnormal. Levels of BOTH light chains may be raised in renal
failure or disorders associated with polyclonal rises in immunoglobulins; the
kappa/lambda ratio is usually normal in these circumstances.
SERUM PROTEIN ELECTROPHORESIS
Performed on all samples sent for immunoglobulin measurement.
See also under immunoglobulins.
Page 16 of 18
Cellular Studies
CD40 LIGAND STUDIES
Sample - Lithium heparin blood from both patient AND a healthy control.
Prior arrangement with the laboratory is essential.
Indicated in patients suspected of having Hyper IgM Syndrome.
LYMPHOCYTE FUNCTION
Sample - Lithium heparin blood from both patient AND a healthy control
Prior arrangement with the laboratory is recommended.
Lymphocyte proliferative assays are indicated in the investigation and assessment of
cellular immunodeficiency.
LYMPHOCYTE PHENOTYPING/SUBSETS
Sample - 4mls EDTA blood (purple top) to reach laboratory within 20 hours & before
3pm on Fridays. Do not refrigerate samples.
Indicated in the evaluation and monitoring of primary and secondary immunodeficiency
disorders. Please note that a CD4 count is an unreliable and unacceptable alternative to
HIV testing. Prior arrangement with the laboratory is recommended unless undertaking
routine monitoring of known immunodeficiency patients.
NEUTROPHIL FUNCTION
Sample - 4mls EDTA (purple top) from both patient AND a healthy control
Sample to reach laboratory before 3.30pm on day of venepuncture & before 3pm on
Fridays. Prior arrangement with the laboratory is recommended.
Assessment of neutrophil respiratory burst (replaces the NBT test) is indicated for the
investigation of suspected Chronic Granulomatous Disease (CGD). Note - neutrophil
function cannot be reliably assessed if the neutrophil count is less than 1 x 109/L.
Page 17 of 18
GUIDE TO APPROPRIATE INVESTIGATIONS
Allergy
Allergen specific IgE - must specify allergen(s)
Anaesthetic reactions
3 samples ~30 mins, 1-3 hrs, 24 hrs after onset of reaction
Suggest use proforma request form.
UK Guidelines http://www.aagbi.org/pdf/anaphylaxis.pdf
Angioedema (no urticaria)
C1 inhibitor, C3, C4
Arthritis
ANA, Rheumatoid factor
Autoimmune liver disease
Autoab screen (mitochondrial, smooth muscle, LKM)
ANA, Immunoglobulins
Coeliac Disease
Tissue transglutaminase IgA abs (TTG abs)
If known IgA deficiency – Endomysial IgG abs
If suspected IgA deficiency – TTG & Immunoglobulins
Connective tissue disease
Initial screen – ANA, C3 & C4
Monitoring SLE - ANA, C3 & C4
Pregnancy –ANA, C3 & C4, ENA, cardiolipin abs
Glomerulonephritis (acute) ANCA, ANA, GBM, C3 & C4, Immunoglobulins
Consider cryoglobulins
Immunodeficiency
Contact laboratory / medical staff for advice
Immunoglobulins
Functional abs
CH100/AP100
Cellular studies
Lymphoproliferative disease Immunoglobulins & electrophoresis
Urine for BJP
Urticaria
Allergen specific IgE rarely helpful unless intermittent
short episodes and possible trigger identifiable from history
Patient information leaflet at
www.bad.org.uk/patients/disease/urtucaria
Guidelines for diagnosis and management at
www.bad.org.uk/doctors/guidelines/urticaria.pdf
Vasculitis
ANCA, ANA, C3 & C4, Immunoglobulins
Consider cryoglobulins. Cardiolipin abs, GBM abs
Page 18 of 18