Blood Changes in Infection and Inflammation Flashcards
What factors affect the normal range of the FBC
Gender Age Ethnicity Geographical location (due to O2) Pregnancy Smoking Exercise Obesity
What are the ranges that are different in both males and females
- Hb g/l
- Basophil x10 9/l
Male
- Hb => 130-170
- Basophil => 0.00
Female
- Hb => 115-145
- Basophil => 0.03
What are the ranges for that are the same in both males and females
- MCV fl
- RDW
- platelets x10 9/l
- WBC x 10 9/l
- neutrophils x10 9/l
- lymphocytes x 10 9/l
- monocytes x 10 9/l
- eosinophils x 10 9/l
- MCV => 82-98 (average volume of cell)
- RDW => 9.9 - 15.5 (measure variation in RBC vol)
- platelets => 150-400
- WBC => 4-11
- neutrophils => 2.2 - 6
- lymphocytes => 1.1 - 3.5
- monocytes => 0.2 - 0.6
- eosinophils => 0.02 - 0.67
What cells can you see on a normal blood film?
Describe the abundance and shapes of each cell
Many enucleated RBCs
Neutrophils => sparse, 3 nuclei
Band neutrophil => rare, horseshoe nuclei
-presence indicates increased BM release of WBCs, immature neutrophils
Monocyte => rare, kidney nucleus Lymphocyte => rare, circular nucleus Eosinophils => rare, red granular appearance, multinuclear Basophil => rare, can only see granules Platelets => v small, spherical
Describe the function of each leukocyte
- neutrophils
- eosinophils
- basophils
- monocytes
- lymphocytes
Neutrophils
-innate, phagocytosis
Eosinophils
-parasite attach, involved in allergic reactions
Basophils
-histamine, heparin release in allergies
Monocytes
- slow response but in innate, phagocytosis
- communicate between innate and adaptive
Lymphocytes
- B cells => AB prod
- T cells => cell mediated attack
Differentials of lymphocytosis
- what is lymphocytosis
- viral
- bacterial
- tissue
- stress
- smoking
- allergies
- splenectomy
- haematological malignancies
What would this look like on a blood film
High lymphocyte count Reactive lymphocytes (large with irregular shape)
Viral
-measles, chicken pox, flu, EBV, CMV
Bacterial
-pertussis, brucellosis, TB
Tissue infarction
-MI, PE
Stress
-MI, cardiac arrest, trauma, obstetric complications
Smoking
-Tcells common, Bcells uncommon
Allergies, splenectomy
Haematological malignancies
- chronic lymphoproliferative
- lymphoma
- ALL
Differentials of red cell agglutination
-VITAMIN CDEF
What would this look like on a blood film
Clumps of RBCs
Infection/inflammation
-EBV, HIV, mycoplasma
Autoimmune
-RA, SLE
Idiopathic
Neoplastic
- CLL
- Waldenstroms macroglobulinemia
What signs, presentation and investigation results would indicate EBV infection?
Sore throat
Enlarged cervical lymph nodes
Fatigue
Hb => low (red cell agglutination)
Lymphocytes => high
Platelets => low (immune thrombocytopenia)
IgM positive (specific for the i antigen on RBCs)
Hepatosplenomegaly
Transaminitis => elevated liver enzymes
PCR for EBV DNA
Differentials for neutrophilia
- what is neutrophilia
- VITAMIN CDEF
What might you see on a blood film
High neutrophils
- left shifted (increase in band cells)
- toxic granulation
- (increased ER => Dohle)
- (increased phagocytosis => vacuolation)
- leukoerythroblastic (more nucleated RBC, immature WBCs)
Vascular
- MI, PE
- acute haemorrhage
Iatrogenic/idiopathic
-CS, adrenaline, lithium
Trauma
- surgery, burns
- acute hypoxia
Autoimmune
-RA, UC, scleroderma
Inflammatory/infective
-bacterial, viral, fungal
Neoplastic
-myeloproliferative neoplasm
Congenital
Endocrine/environmental
-smoking
What signs, symptoms and investigation results would indicate bacterial sepsis
Fever, hypotension, tachycardic
WBC => high
Neutrophils => high
Lymphocytes => high
Platelets => low or high
Hb => low
- due to BM suppression
- haemolysis
- DIC
Blood count, blood film changes
- neutrophilia (toxic granulation, left shift)
- leukoerythroblastic
- thrombocytopenia or thrombocytosis
What exogenous structures could you find on the blood film
What other blood count and blood film changes
Hb => low Platelets => low Lymphocytes => high or low Neutrophils => acute increase, then falls Monocytes => high
Organisms
Headphone shaped structures in RBC
What are the differentials for red cell fragments
What is the pathophysiology behind this
-VITAMIN CDEF
Endothelial damage and fibrin deposition in capillaries
Vascular
- Haemangiomas
- Thrombotic thrombocytopenia purpura
- Malignant HTN
- infection => haemolytic uremic syndrome => DIC
Iatrogenic/idiopathic
-Ciclosporin, clopidogrel, quinolones
Autoimmune
-Scleroderma, SLE
Inflammatory/infective
-infection (bacterial, viruses) => haemolytic uremic syndrome => DIC
Neoplastic
-cancer => haemolytic uremic syndrome => DIC
Congenital
-Microangiopathic haemolytic anaemia
Functional
- HELLP
- prosthetic valves
What are the signs, symptoms and investigation findings of haemolytic uraemic syndrome (food poisoning)
-what would you find on a blood film
Food bourne bacterial, viral infection =>
Diarrhea, bloody vomiting
Poor urine output (due to clots clogging up kidneys)
Drowsy (uremia)
Hb => low
Platelet => low
Neutrophils => high
Microspherocytes (round RBCs)
Red cell fragments (schistocytes)
Nucleated RBCs (come out early of BM to compensate for anemia
What are the differentials for monocytosis
-VITAMIN CDEF
Vascular
-MI, PE
Infective/inflammatory
-TB, syphillis
Autoimmune
- Crohns, UC
- RA, SLE
Neoplastic
-chronic myelomonocytic leukemia
What are the differentials for lymphopenia
-VITAMIN CDEF
Idiopathic/iatrogenic
-steroids, chemotherapy
Autoimmune
-SLE, RA, sarcoidosis
Infective/inflammatory
-HIV, acute infections
Neoplastic
-Non Hodgkin, Hodgkin lymphoma
Functional
-anorexia, alcohol, exercise
How would chronic TB present on a blood film
What are the signs, symptoms and investigation findings
Generally unwell, chronic cough with blood
Weight loss
Hb => low (anemia of chronic disease)
monocytes => high
lymphocytes => low
platelets => low
Monocytes with some nucleated RBCs
How would HIV present on a blood film
What are the signs, symptoms and investigation findings
Generally unwell
Weight loss
Pancytopenia (low RBC, WBC, platelets)
=> AI haemolysis, immune thrombocytopenia, thrombotic thrombocytopenia purpura
Lymphopenia (CD8 directed CD4 killing)
What are the differentials for eosinophilia
-VITAMIN CDEF
-what is the most common cause
How would this present on a blood film
Eosinophils not normally found in blood film-many red granules
-MOST LIKELY TO BE A PARASITIC INFECTION, MORE COMMON IN IMMUNOSUPPRESSED
Iatrogenic/idiopathic
-drug hypersensitivity
Autoimmune
- SLE, RA, systemic sclerosis
- Churg Strauss
- Crohns, UC
Infective/inflammatory
- parasitic
- allergy
Neoplastic
- chronic eosinophilic leukemia
- chronic myeloid leukemia
- Hodgkin/Tcell lymphoma
- acute lymphoblastic leukemia
What is cryoglobulinaemia
What are the 3 common causes
How would this appear on a blood film
Immunoglobulins that precipitate below body temperature
- polyclonal or monoclonal
- block small blood vessels => vasculitis, joint pain, peripheral neuropathy (renaulds)
AI
Hep C
Lymphoproliferative disorders
Cryoglobulins overlie RBC, gives edges an irregular appearance
What are the differentials for haemolysis
What is the pathophysiology
RBCs being destroyed too quickly
-causes are generally acquired
Vascular
-microangiopathic haemolytic anemia
Iatrogenic/idiopathic
- drugs
- paroxysmal nocturnal haemoglobinuria (mutation)
Trauma
- severe burns
- snake venom
Autoimmune
-AI diseases
Metabolic
-G6PD deficiency
Congenital
- inherited membrane disorders
- inherited haemoglobinopathies
Functional
-transfusion reaction
What is a common cause of food poisoning
-where can this pathogen be found
What are the signs and symptoms
What are the complications
Clostridium perfringens
- anaerobic gram +ve rod (can be seen in neutrophils
- often found in soil, decaying vegetation
- produces toxins and gas
Hb => low (spherocytes, due to membrane defect)
WBC => high
Neutrophils => high
Lymphocytes => high
Platelets => low (prolonged coagulation tests)
Can cause severe infections
- gas gangrene
- septic shock
- myonecrosis
- liver abcess
- intravascular haemolysis
What is anaemia of inflammation
Why does this happen
What would this look like on a blood film
Linked to chronic inflammatory disease
-inflammatory cytokines suppress erythropoesis (reduced EPO production, responsiveness) => incresed leukopoeisis in BM
- cytokines cause increased liver hepcidin production=> renal damage => decreased hepcidin excretion
- also promotes macrophage uptake of Fe => less available for RBC production
Leads to reduced RBC lifespan => increased macrophage activation
Red cell rouleaux (stacked RBC)
What would the FBC and iron studies look like in Fe deficiency anemia
- Hb
- MCV
- serum Fe
- ferritin
- transferrin saturation
- total iron binding capacity
- soluble transferrin receptor/log serum ferritin
- BM Fe
- platelets
- CRP
Hb => low MCV => low serum Fe => low ferritin => low transferrin saturation => low total iron binding capacity => high soluble transferrin receptor/log serum ferritin => high BM Fe => absent platelets => normal or high CRP => normal
What would the FBC and iron studies look like in anemia of inflammation
- Hb
- MCV
- serum Fe
- ferritin
- transferrin saturation
- total iron binding capacity
- soluble transferrin receptor/log serum ferritin
- BM Fe
- platelets
- CRP
Hb => low MCV => normal or low serum Fe => low ferritin => normal or high transferrin saturation => low total iron binding capacity => normal or low soluble transferrin receptor/log serum ferritin => normal BM Fe => present and high platelets => normal or high CRP => high
What are the differentiating FBC and iron study results that will tell you if the anemia is caused by Fe deficiency or inflammation?
Ferritin Transferrin saturation Total Fe binding capacity Soluble transferrin receptor Soluble transferrin receptor/log serum ferritin BM Fe CRP
What are the characteristic FBC features in liver failure
What might you see on a blood film?
MCV => high
platelets => low
anemia with acanthocytes (irregular stars) and target cells
neutropenia
What are the characteristic FBC features in renal failure
anemia
platelet dysfunction. platelet count may be normal
echinocytes (regular projections)
