Sickle Cell Anaemia — Symptoms, Diagnosis and Long-Term Management
A Condition That Demands Early Recognition and Lifelong Attention
Sickle cell anaemia is one of the most significant inherited blood disorders in the world — and while its prevalence in Pakistan is lower than in sub-Saharan Africa, the Middle East, and parts of South Asia, it is neither rare nor adequately recognised in clinical practice across Lahore. Patients with sickle cell disease frequently experience years of misdiagnosis, inadequate pain management, and preventable complications before receiving the accurate diagnosis and specialist care their condition requires.
At Alnoor Diagnostic Centre in Shadman, Lahore, we provide the haematological investigations — including HPLC testing — that identify sickle cell disease and sickle cell trait accurately and promptly, supporting the haematologists and clinicians across the city who manage these patients throughout their lives.
What Is Sickle Cell Anaemia — The Biology Explained
Normal red blood cells are round and flexible — shaped like biconcave discs that can squeeze through even the smallest capillaries without difficulty, delivering oxygen to every tissue. This flexibility is possible because of the normal haemoglobin — HbA — packed within each cell. In sickle cell anaemia, a single point mutation in the beta-globin gene produces an abnormal haemoglobin called HbS. When HbS releases oxygen in the tissues, it polymerises — its molecules link together into long, rigid chains that distort the red cell from its normal disc shape into the characteristic elongated, crescent shape that gives the disease its name.
These sickle-shaped cells are rigid and inflexible. They cannot navigate narrow capillaries smoothly. They stick to vessel walls, aggregate with each other, and obstruct blood flow in the small vessels of any organ in the body. This vascular obstruction — called vaso-occlusion — is responsible for the most characteristic and most debilitating feature of the disease — the sickle cell pain crisis. It is also the mechanism through which sickle cell disease damages organs progressively over a lifetime.
Sickled cells are also fragile. They haemolyse — break apart — far more rapidly than normal red cells, surviving only ten to twenty days compared to the normal red cell lifespan of one hundred and twenty days. The bone marrow cannot produce red cells fast enough to replace them, producing a chronic haemolytic anaemia that is a constant feature of the disease regardless of crisis activity.
Sickle Cell Disease vs Sickle Cell Trait — An Essential Distinction
Sickle cell anaemia — also called HbSS disease — occurs when a person inherits the HbS mutation from both parents. Both beta-globin genes carry the sickle mutation, meaning virtually all haemoglobin produced is HbS. These patients have the full clinical disease with chronic anaemia, recurrent pain crises, and progressive organ damage.
Sickle cell trait — HbAS — occurs when the HbS mutation is inherited from one parent and a normal beta-globin gene from the other. These individuals produce both HbS and normal HbA — approximately 40 percent HbS and 60 percent HbA. Under normal circumstances they are entirely asymptomatic and lead completely normal lives. Their red cells do not sickle under physiological conditions because the presence of normal HbA prevents polymerisation.
The clinical importance of sickle cell trait is reproductive rather than personal. When two sickle cell trait carriers have children, each pregnancy carries a one in four chance of producing a child with sickle cell anaemia. Identifying carrier couples through premarital or pre-pregnancy screening is therefore the most important preventive intervention available.
Symptoms of Sickle Cell Anaemia — What Patients Experience
Chronic haemolytic anaemia — The constant destruction of sickled red cells produces a persistent anaemia that most patients with HbSS disease learn to live with as their baseline. Haemoglobin levels typically range from six to nine grams per decilitre — significantly below normal — producing chronic fatigue, pallor, reduced exercise tolerance, and breathlessness. Because this anaemia develops gradually from infancy, patients often adapt to it and do not recognise its full impact on their functional capacity until they experience correction.
Vaso-occlusive pain crises — The defining symptom of sickle cell disease is the pain crisis — episodes of severe, acute pain caused by microvascular obstruction in bones, joints, and organs. Pain crises can be triggered by dehydration, cold temperatures, infection, physical exertion, emotional stress, or high altitude — or can occur with no identifiable trigger. The pain is typically described as deep, severe, and constant — affecting the back, chest, abdomen, and limbs in various combinations. In children, dactylitis — painful swelling of the hands and feet from vascular obstruction in the small bones — is frequently the first manifestation of the disease and an important early clinical clue.
Acute chest syndrome — One of the most dangerous acute complications, acute chest syndrome involves new infiltrates on chest imaging combined with fever, chest pain, and respiratory symptoms. It can be triggered by infection, fat embolism from bone marrow infarction, or in-situ sickling in the pulmonary vasculature. It is a leading cause of death in sickle cell disease and requires urgent recognition and aggressive management including transfusion and respiratory support.
Stroke — Sickling in the cerebral vasculature causes stroke in a significant proportion of patients with HbSS disease, with peak risk in childhood between the ages of two and nine. Transcranial Doppler ultrasound screening identifies children at highest stroke risk — those with elevated cerebral blood flow velocities from vessel narrowing — who benefit from prophylactic chronic transfusion therapy. Stroke in a young child or adult without conventional cardiovascular risk factors should always prompt evaluation for sickle cell disease in Pakistan’s patient population.
Splenic sequestration — In young children with sickle cell disease, the spleen can rapidly sequester a large proportion of the circulating blood volume, causing sudden severe anaemia, hypovolaemia, and potentially cardiovascular collapse. Splenic sequestration is a paediatric emergency requiring immediate recognition and management. With recurrent episodes and progressive splenic infarction, the spleen eventually becomes non-functional — a state called autosplenectomy — leaving patients permanently susceptible to infection from encapsulated organisms including Streptococcus pneumoniae.
Chronic organ damage — Over years and decades of recurrent vaso-occlusion and haemolysis, sickle cell disease damages multiple organ systems progressively. Avascular necrosis of the femoral and humeral heads from bone infarction causes chronic joint pain and disability. Chronic kidney disease develops from repeated renal microvascular injury. Proliferative sickle retinopathy threatens vision. Pulmonary hypertension — elevated blood pressure in the pulmonary circulation — is a serious long-term complication carrying significant mortality risk. Cardiomegaly from chronic anaemia and increased cardiac output is universal.
Jaundice and gallstones — The continuous haemolysis releases large amounts of bilirubin — the breakdown product of haemoglobin — into the circulation. Bilirubin is processed by the liver and excreted in bile. In sickle cell disease, the volume of bilirubin produced overwhelms the normal system, causing chronic mild jaundice and the formation of bilirubin gallstones — pigment stones — at a much younger age than in the general population.
Diagnosis — How Sickle Cell Disease Is Identified
Newborn screening — The ideal point of diagnosis is at birth, before any complications have occurred. Newborn heel prick screening programmes that include haemoglobinopathy testing by HPLC identify affected infants immediately, allowing prophylactic penicillin, pneumococcal vaccination, and parent education to begin before the first clinical crisis occurs. Newborn screening for sickle cell disease is standard practice in high-income countries and is increasingly advocated in Pakistan given the disease’s prevalence.
HPLC — High Performance Liquid Chromatography — HPLC is the gold standard investigation for sickle cell disease diagnosis at any age. It separates and quantifies all haemoglobin fractions present in a blood sample — HbA, HbS, HbF, HbA2, and any structural variants — producing a precise quantitative analysis that identifies the specific haemoglobin genotype. In HbSS disease, HPLC shows a predominance of HbS with absent or markedly reduced HbA and elevated HbF. In HbAS trait, HPLC shows approximately 40 percent HbS alongside normal HbA quantities. The test is reproducible, rapid, and unambiguous in its identification of sickle haemoglobin and its distinction from other haemoglobin variants.
Complete blood count and peripheral film — The CBC in sickle cell disease shows a chronic normocytic anaemia with elevated reticulocyte count — reflecting the accelerated red cell production attempting to compensate for haemolysis. The peripheral blood film shows sickle cells, target cells, polychromasia from reticulocytosis, and nucleated red cells in more severe cases. These findings in a patient from an ethnically appropriate background prompt HPLC confirmation immediately.
Solubility testing — The sickling solubility test is a simple, rapid screening test that identifies the presence of HbS by its insolubility under deoxygenated conditions. It is useful as a rapid screen but cannot distinguish HbSS disease from HbAS trait and cannot identify the specific haemoglobin genotype. HPLC must always follow a positive solubility test to provide the definitive diagnosis.
Long-Term Management — Living Well With Sickle Cell Disease
Hydroxyurea — the most important disease-modifying treatment — Hydroxyurea is an oral medication that increases the production of foetal haemoglobin — HbF — within red cells. HbF does not polymerise with HbS and therefore inhibits sickling when present in sufficient quantities. Patients with higher HbF levels have significantly fewer pain crises, fewer acute chest syndrome episodes, and slower progression of organ damage. Hydroxyurea is the only widely available disease-modifying treatment for sickle cell disease and its benefits are well-established across decades of clinical use. It is significantly underused in Pakistan — many patients who would benefit enormously from it have never been offered it.
Transfusion therapy — Regular blood transfusion — chronic transfusion therapy — is used for specific high-risk indications including primary and secondary stroke prevention, severe or frequent pain crises not controlled by hydroxyurea, and acute chest syndrome. It dilutes the proportion of HbS-containing red cells in the circulation, reducing sickling events. Iron overload from repeated transfusions requires iron chelation therapy — using deferoxamine or oral chelators — to prevent accumulation that damages the heart, liver, and endocrine organs.
Infection prevention — The functional asplenia of sickle cell disease creates permanent susceptibility to overwhelming infection from encapsulated organisms. Lifelong prophylactic penicillin — particularly in children — and comprehensive vaccination including pneumococcal, meningococcal, and Haemophilus influenzae vaccines are essential components of ongoing management. Any fever in a patient with sickle cell disease must be treated as a potential septicaemic emergency.
Pain crisis management — Acute pain crises require prompt, adequate analgesia — the undertreatment of sickle cell pain in emergency settings is a recognised and significant problem globally. Oral and intravenous analgesics, hydration, warmth, and treatment of any precipitating infection form the foundation of crisis management. Patients and families benefit from personalised pain management plans agreed with their haematologist in advance.
Bone marrow transplantation — Currently the only curative treatment for sickle cell disease, bone marrow transplantation from a matched sibling donor offers the possibility of complete cure. It is most successful when performed in childhood before significant organ damage has occurred. The limited availability of matched donors and the procedure’s own risks mean it remains applicable to a minority of patients, but gene therapy approaches — currently in advanced clinical trials internationally — offer the prospect of a broadly applicable cure in the coming decade.
Monitoring for complications — Regular clinical and laboratory monitoring is essential for detecting and managing the chronic complications of sickle cell disease. Annual transcranial Doppler ultrasound in children for stroke risk assessment, regular ophthalmological examination for retinopathy, echocardiography for pulmonary hypertension, renal function monitoring, and bone density assessment form the minimum surveillance programme that specialist haematological care provides.
HPLC Testing at Alnoor Diagnostic Centre, Lahore
At Alnoor Diagnostic Centre in Shadman, Lahore, we provide HPLC haemoglobinopathy testing that accurately identifies sickle cell disease, sickle cell trait, and all clinically significant haemoglobin variants. Our results are precise, promptly reported, and accompanied by the clinical detail that haematologists, paediatricians, and genetic counsellors across the city need for accurate diagnosis and management planning.
Whether you are seeking diagnosis for a child with unexplained anaemia, premarital carrier screening, or confirmation of a suspected haemoglobinopathy in an adult patient, our laboratory team provides the most accurate investigation available.