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Immunology test P-Z

Available tests
Assay Sample Type (Bottle) Reference range Clinical indications Limitations/interferences Technical
information
Clinical
sensitivity & specificity and/or Interpretation
Assay Paraneoplastic
Antibodies (Including: Anti-Yo, Anti-Hu, Anti-Ri,
Anti-amphiphysin)
Sample Type (Bottle) Serum. Reference range N/A Clinical indications Paraneoplastic neurological syndromes (PNS) are remote effects of
cancer on the nervous system.  Examples
include paraneoplastic limbic encephalitis (PLE), subacute sensory
neuronopathy (SSN), paraneoplastic cerebellar degradation (SSN),
paraneoplastic cerebellar degradation (PCD) and paraneoplastic
opsoclonus-myoclonus (POM). Virtually any neoplasm can result in PNS but some
cancers are more frequently encountered such as small cell lung carcinoma,
breast and ovarian and plasma cell tumours. Patients with PNS often present
with neurological symptoms before the underlying cancer is detected so it is
therefore important to test for these antibodies in suspected PNS.  Results may aid direction to the source of
the tumour.
Limitations/interferences Technical
information
Turnaround time:
10 days   Type of investigations:  IIF and Immunoblot
Clinical
sensitivity & specificity and/or Interpretation
Anti-Hu (ANNA-1)
antibodies: associated mainly with small cell lung carcinomas, neurologic
syndromes, include sub-acute sensory neuropathy and paraneoplastic encephalomyelitis.
  Anti-Ri (ANNA2) antibodies:  associated with opsoclonus/myclonus,  paraneoplastic cerebellar degeneration and
brainstem encephalomyelitis. The underlying neoplasm may be neuroblastoma (children),
SCLC (adults) or breast tumours (adults).   Anti-Yo antibodies:  associated with Paraneoplastic Cerebellar Degeneration.
The most frequent underlying tumours are ovary and breast.   Anti Amphiphysin antibodies:  are found in Stiff Person Syndrome and
paraneoplastic encephalmomyelitis and are associated with breast cancer and small
cell lung carcinoma. When found in breast cancer they are associated with the
stiff person syndrome and when found in lung cancer with sensory neuropathy
and paraneoplastic encephalitis.  Anti
CV2/CRMP5 antibodies: are found in peripheral neuropathy, cerebellar ataxia
and limbic encephalitis. They are associated with small cell lung carcinoma
and thymoma  Anti Ma1 antibodies: are
found in paraneoplastic neurological disorder and brainstem encephalomyelitis,
and are associated with various tumours, including lung cancer but not
testicular cancer.  Ma 2/Ta antibodies:
are found in brainstem and limbic encephalomyelitis, and are associated with
testicular cancer.  Anti Tr antibodies:
found in paraneoplastic cerebellar degeneration, and are associated with
Hodgkin’s lymphoma.
Assay Pemphigus/
Pemphigoid Antibodies
Sample Type (Bottle) Serum. Reference range Negative Clinical indications Useful in investigations of blistering autoimmune disease that affects
skin and mucosa membranes. - Pemphigus vulagaris - Bullous pemphigoid -
Epidermolysis bullosa acquisita - Dermatitis herpetiformis - Linear IgA
disease
Limitations/interferences Antinuclear
(ANA), Anti-Mitochondrial (AMA), Anti Smooth muscle (ASMA) and skeletal
muscle antibodies may react with the oesophagus substrate and should be
referred to the duty doctor. Blood group Anti-A and Anti-B antibodies give a
staining pattern that mimics the Pemphigus pattern
Technical
information
Turnaround time:
14 days   Type of investigations:  IIF
Clinical
sensitivity & specificity and/or Interpretation
Intra-epidermal
IgG antibodies present in the desmosomes joining the cells which characterise
various clinical forms of Pemphigus, including idiopathic and
penicillamine-induced, react with antigens present on the cell surface of
epidermal keratinocytes. A positive result gives a characteristic “chicken
wire” pattern. A positive result on IIF gives a distinct IgG basement
membrane zone pattern. The Pemphigoid hemidesmosomal antigens have been
identified as BP230 and BP180.
Assay PR3 ANCA
Antibodies
Sample Type (Bottle) Serum. Reference range 0-1.9 iu/ml Clinical indications Confirmatory test for the presence of anti-PR3 antibodies in ANCA
positive samples, identified by indirect immunofluorescence. C-ANCA positive—
PR3-ANCA: This result occurs in active Polyangitis with granulomatosis
(Wegener's granulomatosis), microscopic polyangiitis (and its renal-limited
variant), and Churg-Strauss syndrome. Patients with systemic vasculitis in
whom ANCA recur are more likely to relapse C-ANCA positive—PR3-ANCA negative
and MPO-ANCA negative: This result may occur in treated, inactive, or relapsing
Polyangitis with granulomatosis (Wegener's granulomatosis), microscopic
polyangiitis (and its renal-limited variant), and Churg-Strauss syndrome.
This combination can also be seen in patients with chronic infections.
Limitations/interferences Technical
information
Turnaround time:  1 day (urgent 4hrs)   Type of investigations: FEIA
Clinical
sensitivity & specificity and/or Interpretation
International
multi-centre studies indicate that the presence of ANCA detected by both IIF
and ELISA (CANCA / PR3-ANCA & P-ANCA / MPOANCA) is very strongly linked
to the presence of small vessel vasculitis. Specificity = 66% for GPA; 26%
MPA
Assay Pancreatic
islet cell Antibodies
Sample Type (Bottle) Serum. Reference range N/A Clinical indications Presence of islet cell antibodies can aid in the diagnosis of type 1
Diabetes Mellitus (IDDM).  Antibodies
are present in up to 70% of new- onset diabetes but their presence is
transient, often disappearing once the islets have been destroyed.  Various antibody targets (glutamic acid
decarboxylase 65 antibodies (GAD65) and protein tyrosine phosphatase-like
protein (IA2) antibodies) will result in the same staining pattern.  This test can also be useful in testing
first degree relatives of patients with IDDM as the presence of high titre
islet cell antibodies (ICA) confers a risk for development of IDDM. This is
most useful if GAD65 and IA2 antibodies are measured Islet cell antibodies
along with GAD65, insulin antibodies and IA2 antibodies may be of use when
investigating latent autoimmune diabetes of adulthood (LADA). Approximately
10% of patients diagnosed with type 2 diabetes have LADA which requires
insulin therapy. LADA may be distinguished from type 2 diabetes by the
presence of the autoantibodies
Limitations/interferences The presence of
ICA does not always correspond to GAD65 and/or IA2 antibodies due to
different sensitivities of the assays.
Technical
information
Turnaround time:
10 days   Type of investigations: IIF
Clinical
sensitivity & specificity and/or Interpretation
IDDM = 70%
sensitive
Assay Phospholipid
antibodies (Anti-Cardiolipin
and Anti-B2GP1 Abs)
Sample Type (Bottle) Serum. Reference range 0-9 gplu/ml 0-6u/ml
 b2gp
Clinical indications Anti-cardiolipin antibodies (ACA) are associated with anti-phospholipid
syndrome, idiopathic spontaneous abortion and systemic lupus erythematosus
(SLE). The international consensus statement clarifies that anti-phospholipid
syndrome can be diagnosed with: Vascular thrombosis  in any organ or tissue or pregnancy event
(one or more miscarriages after 10th week of gestation, three or more
miscarriages before 10th week of gestation, or one or more premature births
before 34th week of gestation due to eclampsia and persistently positive IgG
or IgM anti-phospholipid antibodies (at moderate-high titre : >40 GPL or
MPL U/mL), or moderate-to-high titre beta-2 glycoprotein antibodies.
Anti-cardiolipin antibodies should be positive on at two occasions at least
12 weeks apart to fulfil the criterion of positive ACA antibodies. IgG
anti-cardiolipin antibodies are the most prevalent and demonstrate the
greatest clinical correlation. The significance of IgM anti-cardiolipin
antibodies is uncertain. All samples positive for anti-cardiolipin
automatically receive anti-B2GP1 tests.
Limitations/interferences ACA are
frequently detected in syphilis, HIV infected patients and other viral,
bacterial and parasitic infections but are not correlated with the thrombosis
risk or haematological manifestations of anti-phospholipid syndrome
Technical
information
Turnaround time:  3 days   Type of investigations:  FEIA
Clinical
sensitivity & specificity and/or Interpretation
Anti-Cardiolipin
(ACA) are not diagnostic in themselves and can be found without a clinical
antiphospholipid syndrome. Lupus anticoagulant (DRVVT) must also be checked
and APS can be present with an isolated positive LA and undetectable ACA.
Cardiolipin antibodies should be repeated at least 12 weeks apart to provide
evidence of a persistent autoantibody
Assay Quantiferon TB Sample Type (Bottle) Plasma **
specific Quantiferon Tubes required Adults and children: 1ml of blood must be
drawn directly into each of the four QuantiFERON-GOLD Plus tubes in order,
which must be all labelled with appropriate patient identifying information
Reference range N/A Clinical indications QuantiFERON®-TB Gold (QFT-G) is an indirect test for latent M.
tuberculosis infection (LTBI). QFT-G have been developed using the
tuberculosis antigens ‘early secretion antigen target 6’ (ESAT6 ) and
‘culture filtrate protein 10’ (CFP-10), which are not present in BCG, and are
found in only a few species of environmental mycobacteria Tuberculosis is a
communicable disease caused by infection with M. tuberculosis complex
organisms (M. tuberculosis, M. bovis, M. africanum), which typically spreads
to new hosts via airborne droplets from patients with respiratory
tuberculosis disease. A newly infected individual can become ill from
tuberculosis within weeks to months, but most infected individuals remain
well. Latent tuberculosis infection (LTBI), a non-communicable asymptomatic
condition, persists in some, who might develop tuberculosis disease months or
years later. The main purpose of diagnosing LTBI is to consider medical
treatment for preventing the development of tuberculosis disease. Until
recently the tuberculin skin test (TST) was the only available method for
diagnosing LTBI. Cutaneous sensitivity to tuberculin develops from 2-10 weeks
after infection. However, some infected individuals, including those with a
wide range of conditions hindering immune functions, but also others without
these conditions, do not respond to tuberculin. Conversely, some individuals
who are unlikely to have M. tuberculosis infection exhibit sensitivity to tuberculin
and have positive TST results after vaccination with bacille Calmette-Guerin
(BCG), infection with mycobacteria other than M. tuberculosis complex, or
undetermined other factors. QFT-G is not licensed for diagnosis of active tuberculosis
and it cannot distinguish active disease and LTBI. Who is eligible for
testing? QFTG can be used in patients who have been evaluated for possible M.
tuberculosis – complex infection or LTBI. In other words it can be used in
all circumstances where the tuberculosis skin test is considered.
Limitations/interferences Specific Sample
requirements:  Adults and children: 1ml
of blood must be drawn directly into each of the four QuantiFERON-GOLD Plus
tubes in correct order: (1) GREY TOP (2) Green TOP (3)Yellow TOP (4)PURPLE
TOP Each individual tube must be all labelled with appropriate patient
identifying information. (Collection tubes available from outpatients
Phlebotomy and Clinical Immunology, CUH). Samples must be delivered directly
to the laboratory and must arrive between 08.00 and 18.00 Monday-Friday.
Samples must be incubated at 37ºC within 16 hrs of collection, and must be
kept at room temperature prior to this. Please contact the laboratory for
further information if requesting test from non-Addenbrookes locations. What
are the current limitations of QFTG test? Specimens for testing must be
transferred to the laboratory for processing within 12 hours of venesection.
The test has not been extensively studied in many groups, such as those with immunodeficiency,
those on immunosuppressive drugs and clinical conditions which may reduce
immunocompetence including diabetes, silicosis, chronic renal failure, and haematological
disorders, or malignancy. The test has not been extensively evaluated in
children or in pregnant women. It has not been extensively tested in those
who have been treated for latent TB infection or tuberculosis disease. The
ability of QFTG test to predict the risk of LTBI progression to tuberculosis disease
has not been determined. The risk may be different in those positive for the
QFTG test than in those with a positive tuberculosis skin test. QFT-G is
highly specific and a positive test is strongly predictive of true infection
with M. tuberculosis complex (MTB). However it cannot distinguish between
latent and active disease.
Technical
information
Turnaround time: 5
days  Type of investigations: ELISA  Must arrive between 08.00 and 18.00
Monday-Friday.
Clinical
sensitivity & specificity and/or Interpretation
The diagnosis or
exclusion of tuberculosis disease, and assessing the probability of LTBI,
requires a combination of epidemiological, historical, medical, radiological
and microbiological findings that should be taken into account when
interpreting test results. See general guidance on the diagnosis and
treatment of tuberculosis disease and LTBI (http://www.cdc.gov/nchstp/tb/) or
the NICE guidance on tuberculosis: http://www.nice.org.uk/guidance/index. QUANTIFERON-TB
Gold results are reported as positive, negative or indeterminate.  1. Positive (ESAT-6 and/or CFP-10 and/or
TB7.7 responsiveness detected): M. tuberculosis infection likely. See text
above  2. Negative (No ESAT-6 or CFP-10
and/or TB7.7 responsiveness detected): M.tuberculosis infection unlikely, but
cannot be excluded especially when: a. any illness is consistent with tuberculosis
disease b. likelihood of progression to disease(e.g. because of
immunosuppression) is increased. See text above  3.Indeterminate Test not interpretable.
Unable to determine a result due to lack of
Assay RAST test
(Specific IgE)
Sample Type (Bottle) Serum. Reference range Kua/l  Grade 0:  <0.35 Grade 1:  0.35-0.70 Grade 2: 0.70 - 3.5  Grade 3: 3.5 - 17.5  Grade 4: 17.50 - 50.0 Grade 5: 50.0 - 100.0
Grade 6: >100.0 Please refer to table 4 for list of useful components
Clinical indications Limitations/interferences It is essential
that the results are interpreted alongside a full allergic history and any
tests that have been performed, such as skin prick tests
Technical
information
Turnaround time:
3 days   Type of investigations: FEIA
Clinical
sensitivity & specificity and/or Interpretation
Bee and Wasp
Venom Specific IgE tests are available. However it is strongly recommended
that these patients who are at risk of anaphylaxis after a sting should have
a clinical evaluation by Dr Ewan in the Allergy Clinic as desensitisation is
an effective therapy. In cases of drug sensitivity (e.g. antibiotic,
anaesthetic agents) it is advisable to discuss the case with Dr P.Ewan or
Dr.S.Nasser. RAST testing for specific IgE to penicillin is not completely
reliable for diagnosing immediate type hypersensitivity to this drug. Sampson
HA, Ho DG. Relationship between food-specific IgE concentrations and the risk
of positive food challenges in children and adolescents. J Allergy Clin
Immunol 1997;100:444-1
Assay Rheumatoid
factor (performed
in biochemistry)
Sample Type (Bottle) Serum. Reference range 0- 14 iu/ml Clinical indications In Rheumatoid Arthritis, the presence of a high titre RF at onset is of
some predictive value as these patients have a worse prognosis than
seronegative patients and are more likely to suffer from systemic
manifestations of the disease than those who are RF negative. This test is of
no value in monitoring RA; use CRP instead. 
A negative test for RF can be helpful in the differential diagnosis of
rheumatic diseases as they are not usually detected in rheumatic fever, gout,
Reiter's syndrome, ankylosing spondylitis, osteoarthritis, psoriatic
arthritis and Juvenile Chronic Arthritis. Rheumatoid Factors are
immunoglobulins which react with IgG and are found in a variety of conditions
(viral infections, chronic bacterial infections, connective tissue diseases,
lymphoproliferative disorders and low titres may be found in normal elderly
people) and by themselves are of low diagnostic value.
Limitations/interferences Technical
information
Turnaround time:
1 day   Type of investigations:
Turbidimetry
Clinical
sensitivity & specificity and/or Interpretation
Positive rheumatoid
factor is not specific for rheumatoid arthritis, and can be found in other
connective tissue diseases (e.g. Sjogren's, lupus), infections, and in up to
15% of the normal population. Interpretation of Rheumatoid factor in patients
suspected with Rheumatoid Arthritis: Result Relative risk of Rheumatoid
arthritis 25-50 Iu/ml 3.6 (95% Confidence interval: 1.7-7.3) 50-100 IU/ml 6
(95% Confidence interval: 3.4-10) >100 IU/ml 26 (95% Confidence interval:
15-46) (Reference: BMJ 2012 , vol 345, e5244)
Assay SARS-
CoV-2-IgG
Sample Type (Bottle) Serum. Reference range N/A Clinical indications This test is not the front line assay for Sars-Cov-2 antibody
measurement. For routine antibody levels please see SARS-CoV-2 Total
Antibody.   Measuring  serum antibodies  to 
the  SARS-CoV-2  (COVID-19)  virus 
is  useful  to assess 
if patient  have  been infected with this virus. It is of use
to confirm infection in suspected PCR/RNA+ individuals, but in particular in
symptomatic individuals who have been found to be negative on PCR/RNA
testing. It can be used to screen for 
evidence  of  exposure 
in  asymptomatic  individuals 
as  in  most 
cases  the  virus 
will  not  be 
detectable anymore.
Limitations/interferences Negative results
may occur in patients with immunodeficiency  
Plasma, heat inactivated serum unsuitable. Reject heavily haemolysed
or lipaemic samples. Ideally, samples for this assay should be taken 2 weeks
post disease onset
Technical
information
Turnaround time:
21 days   Type of investigations:
multiplexed  particle-based  flow 
cytometry
Clinical
sensitivity & specificity and/or Interpretation
This assay has
been validated in patients with clinically confirmed COVID-19 and SARS CoV-2
PCR positivity from upper respiratory tract swabs.  The assay in this cohort has a sensitivity
of 84% and specificity of 100%. At present there is no data for other
clinical groups.   A positive result does
not confirm protection against SARS CoV-2 infection, or the ability of the
antibody to neutralise the SARS CoV-2 virus.  The cross reactivity of this assay for
antibodies raised against other corona viruses is yet to be established, but
a control group of sera obtained pre-2018 were negative for antibodies.  Management decisions must continue to be
based on clinical presentation and SARS CoV-2 PCR result as per established
CUH guidelines.
Assay Scleroderma
antibodies
Sample Type (Bottle) Serum. Reference range N/A Clinical indications Scl-70,CENP A,CENP B RP11,RP155,Fibrillarin,NOR90,Th/To, PM-Scl100,
PMScl75, Ku, PDGFR, Ro-52, are scleroderma specific and/or associated
antibodies which can be tested for by immunoblotting if specifically
requested on clinical grounds, or as a follow-up investigation RNA Polymerase
3 antibodies (RP11 and RP155 subunits) and fibrillarin have a high
specificity for Systemic Sclerosis. Th/To-antibodies are found in patients
with Systemic sclerosis; predominantly the limited cutaneous form but also
with Primary Raynauds phenomenon, SLE, Polymyositis and RA. NOR-Nucleolar
Organising Region 90 antibodies are rare and are associated with patients
with Scleroderma and Raynaud’s phenomenon.
Limitations/interferences This test will be
accompanied by a ANA HEp-2 which is essential for the interpretation of the
myositis autoantibody line blot assay
Technical
information
Turnaround time:
14 days   Type of investigations:
Immunoblot
Clinical
sensitivity & specificity and/or Interpretation
N/A
Assay Serum Free
light chains
Sample Type (Bottle) Serum. Reference range 3.30 – 19.4 mg/l
(Serum kappa free light chain) 5.71 – 26.3 mg/l (serum lambda free light
chain) 0.26 – 1.65 kappa:lambda ratio
Clinical indications Guidelines for the management and monitoring of myeloma suggest that
serum FLCs may be useful in monitoring free light chain only myeloma.
Abnormal FLC levels and ratio can be found in multiple myeloma, Bence Jones
proteinuria, non-secretory myelomas, free light chain disease and primary
amyloidosis. Serum concentrations of FLCs are dependent on the balance
between production and renal clearance. Elevated levels of both free kappa and
free lambda light chain can be found in renal failure (due to decreased loss
in urine) or in inflammation (increased synthesis). In these conditions kappa
and lambda are affected equally.
Limitations/interferences Haemolysis,
grossly lipaemic or icteric samples.
Technical
information
Turnaround time:  5 days   Type of investigations: Turbidimetry
Clinical
sensitivity & specificity and/or Interpretation
N/A
Assay Serum protein
electrophoresis/ myeloma screen
Sample Type (Bottle) Serum. Reference range Normal
electrophoretic pattern
Clinical indications Immunochemical measurement of immunoglobulins cannot substitute for
electrophoresis in the diagnosis of paraproteins and should be done together.
Current guidelines for the investigation of Multiple Myeloma and Monoclonal
Gammopathy of Uncertain Significance (MGUS) recommend that serum and urine  electrophoresis should be used in the
detection of B cell malignancy or plasma cell dyscrasia. This should be
followed by immunofixation if there are any monoclonal bands present, or
there are no bands present but there is high suspicion of B cell malignancy.
The guidelines also suggest that serum free light chains may be useful in
monitoring free light chain only myeloma. The concomitant use of serum free
light chain measurements in specific circumstances is advocated, but it
cannot currently replace current methods. Guidelines for the analysis of
Bence Jones Protein suggest that urine electrophoresis is useful when myeloma
is diagnosed, during follow-up and in the investigation of patients who have
suspected monoclonal gammopathy. Reductions in immunoglobulin levels can
indicate primary immunodeficiencies (PID) or other severe secondary
immunosuppression depending on the clinical history of the patient. Exclusion
of other causes, results of other laboratory tests, and whether they fit the
European Society for Immunodeficiencies (ESID) criteria for diagnosis should
be considered during diagnosis.
Limitations/interferences Technical
information
Turnaround time:
4 days   Type of investigations:
Capillary zone electrophoresis (CZE) and immunofixation
Clinical
sensitivity & specificity and/or Interpretation
Each trace is
interpreted individually in conjunction with clinical details and associated
analysis.
Assay Serotype
Specific Pneumococcal Antibodies
Sample Type (Bottle) Serum. Reference range Putative
protective level 0.35 µg/ml
Clinical indications Antibodies to 13 pneumococcal specific serotypes are measured. This
test is used in the diagnosis of Primary Immune deficiency. This test should
be requested for patients who have clinical history of recurrent infections
and/or evidence of bronchiectasis. 11/13 serotypes tested are contained in
the childhood conjugated pneumococcal vaccine Prevenar13 (introduced in
2010). Protective levels of these show satisfactory response to the T cell
dependent antibody production pathway. All 13 serotypes are contained in the
unconjugated vaccine Pneumovax. Protective response to Pneumovax infers
normal functioning of the T-independent antibody production pathway. Patients
should have this test done in the following clinical circumstances: a)
Patients, especially children, with recurrent bacterial sepsis; particularly
of the upper and lower respiratory tract. b) Patients with invasive disease
caused by encapsulated organisms. c) Patients with selective antibody
deficiency states. d) To assess Immunological reconstitution following Bone
Marrow Transplant. e) Patients with haemoglobinopathies or who have had a
splenectomy should have their levels of antibodies to encapsulated bacteria
(i.e. pneumoccocal and Hib) monitored.
Limitations/interferences Knowledge of
vaccine history is imperative for correct interpretation. Specific clinical
symptoms also advantageous. If a poor response if found, patients will be
required to be vaccinated and retested 4 week post. Specific interpretation
is given for each patient result. Children under the age of 2 years do not
normally mount an immune response to either Pneumovax or to natural exposure.
In contrast, the conjugate pneumococcal vaccine (Prevenar); is fully
immunogenic from birth.
Technical
information
Turnaround time:
15 days   Type of investigations:
Luminex
Clinical
sensitivity & specificity and/or Interpretation
Interpretation of
pneumococcal serotype specific responses in patients under 15 years of age.
For children born since 2006 who have received the UK standard immunisations:
 1. Post immunisation serotype specific
antibody concentration >0.35ug/ml suggests protection against invasive
pneumococcal disease; the concentration of antibody required to protect
against mucosal disease is likely to be greater for most serotypes 2. Most
infants (>90%) develop antibody responses >0.35ug/ml to most of the
vaccine serotypes and this response is generally retained for a least one
year post immunisation. 3. Persistence of antibody response >1year post
immunisation is unclear however routine re-immunisation is not generally
recommended. For children born before 2006 and/or >2 years and immunised
as per UK schedule, who are immunised with Pneumovax:  Aged 2-7 years: 95% of healthy children show
an increased in antibody concentration >0.35ug/ml to at least 6 of the 13
serotypes tested.  Aged 8 years and
older, 95% of healthy children show an increased in antibody concentration
>0.35ug/ml to at least 8 of the 13 serotypes tested. If pneumococcal
responses are impaired as defined above, and the patient has increased
susceptibility to infection, consider referral to a paediatric immunologist
for review. Interpretation of pneumococcal serotype specific responses in
patients above 15 years of age.  This
assay is to be used in the assessment of immunodeficiency and NOT for
predicting protection from pneumococcal sepsis. Antibody responses can only
be interpreted at least 4 weeks post vaccination with Pneumovax. After
immunisation with Pneumovax, antibody responses (>0.35 ug/ml) to less than
7/13 serotypes has a 95% sensitivity and 85% specificity for the diagnosis of
antibody deficiency. The results should be interpreted in the context of the
clinical picture. If there is a high index of suspicion of immunodeficiency; please
contact us to discuss further. If the response to immunisation Pneumovax
results is less than 7/13 serotypes >0.35ug/ml, consider further
immunisation with Prevenar and repeat serology 4 weeks later. If pneumococcal
responses are abnormal as defined above, consider referral to an immunologist.
Note: Prevenar is a more powerful immunogen than Pneumovax and activates T
cell dependent antibody responses. Therefore antibody responses to Prevenar
cannot be used to evaluate thymus independent responses to polysaccharides.
Assay Specific IgG
aspergillus
Sample Type (Bottle) Serum. Reference range 0 – 40 mg/l Clinical indications Allergic broncho pulmonary Aspergillosis. This is a complex
inflammatory response to inhaled spores and is seen in about 1% of asthma
sufferers and up to 15% of patients with cystic fibrosis. Patients have a
characteristic X ray appearance and elevated total IgE, and both specific IgG
and specific IgE to aspergillus fumigatus. Levels of specific IgG have been
defined which make the diagnosis likely. This is >90 mg/L in patients with
cystic fibrosis and >35 mg/L in other patients.
Limitations/interferences Technical
information
Turnaround time:
3 days   Type of investigations: FEIA
Clinical
sensitivity & specificity and/or Interpretation
N/A
Assay Specific IgG
pigeon
Sample Type (Bottle) Serum. Reference range 0 -10 mg/l Clinical indications For suspected bird fanciers lung, the test for IgG antibodies to pigeon
serum is performed. This will detect antibodies to all commonly kept birds
including pigeon, budgerigar, finch, cockatiel, parrot and canary. Levels
above 10 mg/L indicate significant exposure to the antigen.
Limitations/interferences Technical
information
Turnaround time:
5 days   Type of investigations: FEIA
Clinical
sensitivity & specificity and/or Interpretation
N/A
Assay Specific
IgG  Micropolyspora Faeni    Specific IgG Laceyella sacchari
Sample Type (Bottle) Serum. Reference range 0- 22 mg/l      0- 36 mg/l Clinical indications For suspected farmer’s lung, tests are available for IgG antibodies to
Saccheropolyspora reactivirgula (formally Micropolyspora faeni) and to
Laceyella sacchari
Limitations/interferences Technical
information
Turnaround time:
5 days   Type of investigations: FEIA
Clinical
sensitivity & specificity and/or Interpretation
N/A
Assay Striated
muscle antibodies/ skeletal muscle antibodies
Sample Type (Bottle) Serum. Reference range Negative Clinical indications Anti-Striated muscle/skeletal muscle 
antibodies (ASTM) are circulating serum auto antibodies directed
against Striated muscle and are found in Myasthenia Gravis (MG). Their
presence is good evidence of Thymoma in MG patients.
Limitations/interferences Technical
information
Turnaround time:
10 days   Type of investigations:  IIF
Clinical
sensitivity & specificity and/or Interpretation
Sent to Sheffield
Immunology for analysis,  This test
alone should not be considered diagnostic. All other factors including the
clinical history, other serological or biopsy results must be taken into
account.
Assay Tetanus
Antibodies
Sample Type (Bottle) Serum. Reference range Tetanus Minimum
0.1 iu/ml Optimum > 1.0 iu/ml
Clinical indications This test is used to assess the T-cell dependent antibody pathway.
Patients should have this test done in the following clinical circumstances:
a) Patients being investigated to diagnose antibody deficiency. b) To test
immunological reconstitution following Bone Marrow Transplant. e) To assess
whether an individual with uncertain immunisation history is protected from
tetanus.
Limitations/interferences Knowledge of
vaccine history is imperative for correct interpretation. If a poor response
if found, patients will be required to be vaccinated and retested 4 week
post. Specific interpretation is given for each patient result
Technical
information
Turnaround time:
21 days   Type of investigations:
Luminex
Clinical
sensitivity & specificity and/or Interpretation
N/A
Assay Thyroid
peroxidase antibodies (performed in biochemistry)
Sample Type (Bottle) Serum. Reference range 0- 60 iu/ml Clinical indications Anti-thyroid peroxidase antibodies are present in patients with
autoimmune thyroid disease: Grave’s disease (60%), Hashimoto’s (90%) and
primary myxoedema (80%). They may be present without overt thyroid
dysfunction in cases of autoimmune polyendocrine disease High titre thyroid
antibodies are a good predictor for the future development of biochemical
thyroid disease
Limitations/interferences Technical
information
Turnaround time:
1 day   Type of investigations:
Turbidimetry
Clinical
sensitivity & specificity and/or Interpretation
Assay Tissue
Transglutaminase antibody
Sample Type (Bottle) Serum. Reference range IgA 0 – 6 iu/ml  IgG 0 – 7 iu/ml Clinical indications IgA Tissue Transglutaminase antibodies are present in at least 80% of
patients with active coeliac disease. It will be absent in patients on a
gluten free diet. As part of the investigation selective IgA deficiency will
be excluded, with samples giving low responses on the IgA ttg assay
Limitations/interferences Technical
information
Turnaround time:
3 days   Type of investigations: FEIA
Clinical
sensitivity & specificity and/or Interpretation
Sensitivity =
>95%  Specificity = >90%
Assay Thyroid
Stimulating Immunoglobulins (performed in Biochemistry)
Sample Type (Bottle) Serum. Reference range < 0.56 iu/l Clinical indications The hyperthyroidism of Grave’s disease is caused by the presence of
stimulatory IgG antibodies which bind to thyrotrophin (TSH) receptors on the
thyroid follicular cells and cause unregulated stimulation of thyroid hormone
production.
Limitations/interferences This assay
utilizes recombinant human TSH receptors (hTSHR) for the specific detection
of thyroid stimulating autoantibodies. (please note –this is not a TSH
receptor antibody assay which detects both stimulating and inhibitory binding
antibodies)
Technical
information
Turnaround time:
5 days Type of investigations: Chemiluminescence
Clinical
sensitivity & specificity and/or Interpretation
Clinical
sensitivity = 100%  Clinical
specificity = 98.7%   Renato Tozzoli et
al Clin Chem Lab Med 2016
Assay Urine
electrophoresis
Sample Type (Bottle) Urine. Reference range N/A Clinical indications Bence-Jones Protein (free light chains κ or λ) BJP is associated with
multiple myeloma, Waldenstroms macroglobulinaemia, monoclonal light chain
associated amyloidosis and light chain deposition disease. It can also be
seen in lymphoma and leukaemia. This assay is part of both the screen and
follow-up investigations for myeloma.
Limitations/interferences Technical
information
Turnaround time:
5 days   Type of investigations:
Electrophoresis
Clinical
sensitivity & specificity and/or Interpretation
N/A
Assay Voltage Gated
Potassium Channel Associated Protein Profile Antibodies
Sample Type (Bottle) Serum. Reference range N/A Clinical indications CASPR2 auto antibodies are seen in neuromyopathy, Morvan’s syndrome,
limbic encephalitis and epilepsy. About a third of cases can be attributed to
paraneoplastic syndrome, mostly in connection with thymoma.  Autoantibodies against LGI1 can be detected
in limbic encephalitis, Morvan’s syndrome, isolated neuromyotonia, isolated
epilepsy and other neurological syndromes.  of limbic encephalitis. A positive result is
an indication for investigation for a possible tumour.
Limitations/interferences This test may
only be requested on Serum for CSF please see refered tests below
Technical
information
Turnaround time:
14 days   Type of investigations:
Indirect  Immunofluorescence test
Clinical
sensitivity & specificity and/or Interpretation
This test is
indicated in the investigation of Limbic encephalitis (LE) and acquired
neuromyotonia (Isaacs’s syndrome).