At 50 years-the last 13 on ARVs-she is one of the success stories for HIV treatment in Kenya.
Her adherence is excellent, she has no history of coughs, night sweats, back pain or the pricking sensation caused by nerve damage.
That was until two years ago when Anne* (her name has been changed) began complaining of generalised body aches and bone pains.
These symptoms worsened three weeks before her recent admission to hospital and were accompanied by muscle weakness in both the upper and lower limbs.
“Our patient was initiated on highly active antiretroviral therapy (HAART) in 2011 and has been on her drugs with excellent adherence since then,” doctors confirm.
Despite the adherence, she was wasted with a BMI of 17.8 and weighed 48 kilogrammes when she checked in the hospital. She was also immobile due to a recent fall, but all other systemic exams were normal.
However, laboratory investigations revealed significant renal dysfunction. There was a poor waste filtration rate by the kidneys, elevated creatinine levels in the blood, elevated protein (proteinuria) and sugar (glycosuria) in urine, and too little calcium in the blood.
Creatinine is a normal waste product in the body made when you use your muscles and some of the muscle tissue breaks down.
Normally, the kidneys filter creatinine from the blood and remove it through the urine.
Doctors made a diagnosis of Fanconi syndrome, a rare disorder characterised by damage to the tiny tubes inside the kidney. The damage can be caused by certain medicines.
Dr Fredrick Odhiambo, a specialist at the Maua Methodist Hospital in Meru, and his colleagues determined the damage was caused by the common Tenofovir Disoproxil Fumarate (TDF) medicines the woman used to treat HIV.
Tenofovir is one of the newest and more tolerable backbone of HIV treatment around the world. In 2016, the World Health Organization (WHO) recommended Tenofovir based regimen as the first line for adults and adolescents.
“Despite its excellent safety profile and tolerability, TDF is known to cause proximal tubule renal dysfunction,” Dr Odhiambo and his colleagues say in a report they published last week in the Clinical Case Reports journal.
The damage to kidney’s tiny tubes can manifest as Fanconi syndrome (FS), acute kidney injury or chronic kidney disease.
Dr Odhiambo now emphasises the importance of monitoring renal function in clients with HIV.
"Patients on TDF-based regimen are at five times greater risk of developing chronic kidney disease in comparison to patients on a non-TDF-based regimen," he explained.
The prevalence of renal dysfunction induced by TDF is estimated at 5.6 per cent and the risk is increased with advanced age, low BMI, low baseline CD4 count, hypertension and diabetes, he said.
His colleagues and report co-authors are Shallot Nareeba, Grace Mwangeka, Ann Njambi and Vashti Nyakebati.
Upon diagnosis, Anne was switched from TDF to an Abacavir-based regimen. Abacavir is another powerful drug used to treat HIV.
Remarkably, within 11 weeks, her renal function showed significant improvement. Creatinine levels normalised, proteinuria and glycosuria cleared and her muscle strength improved, allowing her to walk with support .
“This case underscores the need for regular renal function monitoring for patients on TDF, especially in resource-limited settings where access to routine tests may be constrained,” Dr Odhiambo said.
The report is titled “Tenofovir induced Fanconi syndrome in a middle age African female from Kenya, East Africa: Case report and brief literature review”.
The National Empowerment Network of People Living with HIV/Aids in Kenya (Nephak), says the government needs to support Kenyans who are ageing with HIV.
“The required renal tests every year are expensive and many people cannot afford them,” Nephak CEO Nelson Otwoma said.
“Many people who have been on HIV treatment for a long time have many comorbidities of non-communicable diseases and cannot afford treatment and tests.”
According to Dr Odhiambo’s team, Anne could not afford the necessary annual renal tests.
In the absence of treatment, Fancomi syndrome leads to chronic renal failure. The treatments for kidney failure are dialysis and a kidney transplant.