What is acute kidney injury?

Acute kidney injury (AKI) is a sudden decrease in the ability of the kidney to filter the blood, resulting in a reduction in urine production. This decrease disturbs the balance of body fluids and electrolytes, causing the body to retain wastes.

Although a problem worldwide, acute kidney injury is more common in Africa than elsewhere. Available data indicates that the disease is common among 10 - 40% of adults in sub-Saharan Africa.

Symptoms and signs of AKI

Most patients do not know that they have an acute kidney injury because the condition does not often present with clinical symptoms. However, the following symptoms might be present in some:

Decreased urine output
Edema: generalized body swelling
Hypertension
Weakness
Nausea
Coma, in severe cases

Classification of AKI

Acute kidney injury is classified based on the location of the cause of the injury. The classifications could be:

Pre-renal AKI - if the cause of the injury is before the kidney
Renal or intrinsic AKI - if the injury is within the kidney
Post renal AKI - if the injury is caused by factors after the kidney, such as the obstruction of the ureter, a tube that carries urine from the kidney to the bladder, by a stone.

Only the intrinsic acute kidney injury represents true kidney disease. Pre-renal and post-renal forms of the disease are the consequences of non-kidney diseases that lead to a decreased glomerular filtration rate (GFR).

Stages of acute kidney injury

There are four main stages in the development of an acute kidney injury:

Initiation
Oligo-anuria
Polyuria
Restitution

These four stages restore kidney functions and should last a maximum period of three months, if the injury does not cause significant damage to the kidney.

However, the injury can progress to a chronic kidney disease if it persists for more than three months.

Causes of AKI in sub-Saharan Africa (SSA)

The most common causes of acute kidney injury in Africa include:

Malaria
HIV
Nephrotoxic agents such as traditional herbal concoctions
Envenomation from snakebite
Chronic conditions like diabetes mellitus and hypertension
Obstetric complications
Use of skin lightening (bleaching) creams containing mercury

Who is at risk of acute kidney injury?

Anyone can come down with acute kidney injury but some classes of people are especially at higher risk. These sets of people include:

People living with chronic illnesses like diabetes mellitus, hypertension, and sickle cell disease
Patients with sepsis
Patients with poorly treated urinary tract infection
People who abuse nonsteroidal anti-inflammatory drugs (NSAIDs)
Elderly patients
People with blocked urinary tract
Users of certain antibiotics like aminoglycosides
Patients with dehydration from diarrhea or exercise
Patrons of traditional practices that involve lacerations of people with unsterilised tools
People observing prolonged fasting without water
Poor people who drink herbal concoctions

Complications of acute kidney injury

When the kidney cannot filter waste and electrolytes from the blood or maintain the water or electrolytes balance due to an injury, the patient may develop complications such as:

Edema: generalized body swelling
Arrhythmia: abnormal heart rhythm
Metabolic acidosis: acid buildup in the blood due to reduced excretion

Vomiting, drowsiness and breathlessness also can occur.

Diagnosis and laboratory tests for AKI

Your doctor may order a range of tests to confirm an acute kidney injury or determine its severity These tests include:

Urinalysis
Blood test
Abdominopelvic ultrasound
CT scan
Biopsy of the kidneys in extreme cases

Treatment for acute kidney injury

Prompt medical treatment is necessary to reverse an acute kidney injury, restore kidney functions, and prevent the injury from progressing to a chronic disease or degenerating into renal failure.

Treatment options include:

Medications to restore fluid and electrolyte balance
Diuretics to help eliminate accumulated waste
Dialysis support for people with severe acute kidney injury
Dietary restrictions, especially from potassium-rich foods like bananas, oranges, spinach, potatoes, and tomatoes

How to prevent acute kidney injury

A healthy lifestyle, balanced diet, and adequate hydration are key to preventing acute kidney injury. These healthy habits can reduce your chances of having an acute kidney injury, but may require you to:

Reduce alcohol intake
Avoid the abuse of NSAIDS like Ibuprofen and aspirin
Exercise regularly

Challenges in the Management of Acute Kidney Injury in Africa

Acute kidney injury is still a major challenge in Africa as compared to other parts of the world. This is due to:

Inadequate facilities and diagnostic tools

Poor communities don't have standard hospitals and laboratories. This makes it difficult for patients to access care on time.

Few specialists, many patients

The number of people with acute kidney injury far outnumbers the number of specialists to care for them. While some patients with the injury may need to see a specialist, those who need specialists must compete with tens of other patients, which may lead to treatment delays and avoidable complications.

Late presentation

Patients with AKI often present late to the clinic due, in part, to poverty, ignorance, and self-treatment. Some patients start with self medications, only to present at the hospital when they don't see any improvement.

Poverty and illiteracy

Poverty and illiteracy go hand-in-hand to complicate AKI care in Africa. Some patients who have AKI and need to see a doctor help don't know they do need medical attention, while those who do may not have the financial means to get well.

High disease burden

African patients are disproportionately affected by AKI, along with other diseases like HIV, malaria, and diarrhoea, and triggers like nephrotoxins (chemicals that hurt the kidneys). This high disease burden increases the risk of worse outcomes for African patients with AKI.

What next?

The high prevalence of AKI in SSA is not solely due to the nature of the condition, but rather a complex interplay of preventable and treatable causes, poor health-seeking behavior, socioeconomic barriers, and systemic healthcare challenges. Addressing these multifaceted issues is crucial to improving the management and outcomes of AKI in the region.
To ensure that AKI incidence is greatly reduced, there’s a need for proper awareness of this disease entity in SSA, especially since a good number of her populace ingest herbal concoctions and the prevalence of malaria with HIV, which are the main culprits of AKI.

The Burden Of Acute Kidney Injury (Aki) In Africa