Improvements in obstetric care have led to the virtual disappearance of pregnancy-related AKI in the industrialized world. Data from a large tertiary care hospital in the eastern part of India have shown that the proportion of obstetric AKI cases remained more or less similar at 11.8% and 12.8% of total cases of AKI over two 13-year time periods (1996−2008 vs. 1983−1995, respectively). A retrospective analysis from Pakistan reported increase in incidence of obstetric AKI in the years 2010–2014 (35.27%) compared with 1990–2010 (21.64%).

The frequency distribution of AKI is bimodal in terms of the duration of gestation. The first peak, seen between 8 and 16 weeks’ gestation, is associated chiefly with induced septic abortions. The incidence of postabortal AKI has decreased since the legalization and regulation of abortions and the wider availability of medical facilities in the recent times. The second peak in obstetric AKI occurs after 34 weeks’ gestation and is related to preeclampsia, eclampsia, abruptio placentae, postpartum hemorrhage, and puerperal sepsis. The incidence of preeclampsia in the Indian population has been reported to be 28.7% in a population-based study. Data from Pakistan, Bangladesh, and Nepal have also suggested sepsis related to abortion or puerperium, hemorrhage, hypotension, and preeclampsia as the main associations of pregnancy-related AKI. The majority of pregnancy-related AKI occurs due to preeclampsia/eclampsia followed by puerperal sepsis and postpartum hemorrhage. Obstetric AKI is the main cause of acute cortical necrosis. ^, Thrombotic microangiopathy is being recognized as one of the important causes of pregnancy-associated acute cortical necrosis. ^, Those women who do not recover kidney function usually undergo contrast-enhanced computed tomography of the kidneys to look for acute cortical necrosis. The characteristic findings include lack of enhancement of renal cortex, medullary enhancement, and absent renal excretion. If this is absent, a renal biopsy is done in such individuals.

The provision of institutional care and early referral for patients with complicated pregnancies to specialized centers is important to ensure better prevention and management of AKI in such settings. Along with community-level interventions, facility enhancement is also required for decreasing pregnancy-related mortality and morbidity. AKI in pregnancy is managed along the usual lines, with additional cause-specific interventions, if any. Pregnancy and kidney disease are further discussed in Chapter 58 .

Acute renal cortical necrosis is the most catastrophic of all types of AKI. Of more than 2900 patients with AKI treated with dialysis over 28 years in a study in northern India, 3.8% were found to have acute cortical necrosis. Obstetric complications were responsible for 56% of all cases of acute cortical necrosis, whereas snakebite accounted for 14%. The most striking feature of this condition is prolonged oliguria or anuria. The study in northern India found that only 17% of patients could discontinue dialysis by the end of 3 months.

PD becomes important in such resource-constrained settings because it requires minimal infrastructure and expertise. When required, and if available, PD is likely to be lifesaving. PD is the preferred modality of choice for AKI in children when surveyed among Indian pediatric nephrologists. There have been several success stories of acute PD being lifesaving in desperate and emergency circumstances. Both rigid and flexible PD catheters can be inserted at the bedside. The cost of acute PD per day is 10 times lesser when compared with continuous renal replacement therapy. Performance of acute PD is a skill that is easily taught and acquired. In fact, many general physicians, especially in the armed forces, who might be posted to far-off places or places where hemodialysis (HD) is not available around the clock, routinely carry out acute PD whenever required. During the COVID-19 pandemic in India, because many patients of COVID-19–related AKI did not tolerate intermittent HD, acute PD was preferred by many nephrologists. ^,

An accurate estimate of the number of patients on the Indian subcontinent who have CKD or need RRT is not available owing to the lack of nationwide registries. A countrywide Indian Chronic Kidney Disease cohort study of early-stage CKD patients is ongoing in India. The study aims to describe the epidemiology of CKD progression and the development of complications such as cardiovascular disease in CKD in developing countries.

A cross-sectional study that screened 5588 adults from different parts of India reported a CKD prevalence of 17.2%, with about 6% having CKD stage 3 or worse. The prevalence of early stages of CKD (stages 1–3) was reported to be about 13.1% to 15% using the Chronic Kidney Disease Epidemiology Collaboration or Modification of Diet in Renal Disease study equation in a cohort of 3398 otherwise healthy adults. Studies from Pakistan, Nepal, and Bangladesh have reported a CKD prevalence of 25.3%, 10.7%, and 13.1% to 16%, respectively, in the general population. A systematic review and meta-analysis of population-level prevalence studies in South Asia reported a CKD prevalence of 14% in general population and 27% to 31% in high-risk population. These figures must be interpreted with caution because of the wide variations in the definition of CKD, study methodology, and sampled population. Few studies have estimated the prevalence of CKD in rural communities. Despite a high prevalence of CKD, there is a low awareness of the disease.

Commonly used formulas for the estimation of the glomerular filtration rate (GFR), such as the Modification of Diet in Renal Disease study equation, have been validated only in small population-based studies in the Indian subcontinent. Differences in body habitus and dietary habits make it likely that these formulas may require further validation and possibly correction factors for the accurate assessment of GFR in this population. The newer race-independent CKD epidemiologic (2021 Chronic Kidney Disease Epidemiology Collaboration estimated GFR creatinine) equation increases the GFR, lowering the estimated kidney disease burden in the Asian Indian cohort.

The crude and age-adjusted incidences of ESKF in India have been estimated to be 151 and 232/million population, respectively. This means that 250,000 to 300,000 new patients need kidney replacement therapy every year. Data on the prevalence of ESKF are not available.

Diabetic kidney disease, previously restricted to high-income urban residents and older individuals, has now emerged as the most important cause of CKD in this region ( Table 77.3 ). According to the Indian CKD Registry, which has information on more than 57,000 patients, diabetes was listed as the primary diagnosis in 31% of cases of CKD. In the Indian Chronic Kidney Disease cohort, diabetic kidney disease is the most common cause of CKD (25%), followed by chronic interstitial nephritis and CKD of unknown etiology (CKDu). In Pakistan, Sri Lanka, and Bangladesh, diabetic nephropathy is an important cause of CKD. The Indian Council of Medical Research–India Diabetes study reported that 11.4%, 15.3%, and 35.5% of the Indian population have diabetes, prediabetes, and hypertension, respectively. The growing incidence of noncommunicable diseases is concerning and is mainly concentrated in the urban population. The high incidence of type 2 diabetes in the Indian population is due to economic growth, rapid urbanization, genetic predisposition, increased insulin resistance, poor physical activity, and high refined cereal intake.

CKDu is an important cause of CKD in this region and is highly prevalent in certain hotspots. Parameswaran and colleagues discovered that CKDu contributes to >50% of the cases of CKD in some cohorts from India. The presentation is usually in the advanced stages. The exact reasons and pathogenesis are unknown; however, the roles of agrochemicals, water quality, heavy metals, and heat stress are implicated. Predominant tubular involvement without glomerular changes is seen in the kidney biopsy specimens. Chapters 74 and 83 discusses this topic in detail.

Low birth weight and early malnutrition, followed by overnutrition in adult life, have been shown to be associated with the development of metabolic syndrome, diabetes, and diabetic nephropathy in an Indian cohort discussed further in Chapter 20 . The finding of a high prevalence of proteinuria and high blood pressure in southern Asian children could be part of this jigsaw puzzle. A high percent of such children can be identified for the first time with CKD. Also not investigated has been the role of dietary habits and indigenous medicines. CKD in individuals with infections such as chronic hepatitis B or C, HIV, and tropical infectious diseases have also been reported. ^,

The mean age of patients with CKD, including those requiring RRT, is generally lower in this region than in other parts of the world. The mean age of Indian patients with CKD is 50.1 ± 14.6 years and two-thirds are males. Poorer female representation in the cohorts might reflect a systematic barrier in presentation to health care facilities for females in India, likely due to sociocultural reasons. A sizable proportion of adults experience rapid GFR decline after diagnosis. Metformin, statins, and renin-angiotensin-aldosterone system blockers are not adequately prescribed in early CKD. Usage of tobacco products and poor glycemic control contribute to the high incidence of tuberculosis in the CKD population. ^, India replaced China to be the country with highest number of CKD-related deaths. The reasons for such high mortality have not been studied.

A large study of more than 5400 kidney biopsy specimens at a south Indian tertiary care center that treats not only patients from India but also those from neighboring countries has provided insight into the range of glomerulonephritis in the region. Primary glomerulonephritis was diagnosed in 71% of all the biopsy specimens. Mesangioproliferative glomerulonephritis without IgA was the most common lesion (20.2%), followed by idiopathic focal segmental glomerulosclerosis (FSGS) (17%), minimal change disease (11.6%), membranous nephropathy (MN) (9.8%), IgA nephropathy (8.6%), and membranoproliferative glomerulonephritis (3.7%). Postinfectious glomerulonephritis accounted for 12.3% of all lesions. A report of 3275 biopsies done between 2006 and 2016 from a tertiary care hospital in northern India reported FSGS to be the commonest morphology (18.2%), followed by MCD (16.8%), MN (16%), and IgA nephropathy (10.4%) among the primary glomerulonephritides. Lupus nephritis (10.6%) and amyloidosis (3.7%) were the commonly reported secondary glomerulonephritides. MN is more common in adults with nephrotic syndrome >40 years. FSGS, MCD, MN, and IgA nephropathy are the common primary glomerulonephritides, and lupus nephritis is the common secondary glomerulonephritis reported from other countries in this region. Secondary amyloidosis is much more common than primary amyloidosis; tuberculosis followed by rheumatoid arthritis are the common etiologies for secondary amyloidosis. ^, The glomerular diseases from the largest published cohorts in the Indian subcontinent are listed in Table 77.4 . I-TANGIBLE (Indian TrANslational GlomerulonephrItis BioLogy nEtwork) is a newly formed network of investigators in glomerular diseases to collect information in a systematic fashion to understand the clinical outcomes, answer translational research questions better, and identify and recruit patients for clinical trials.

The most common causes of renovascular hypertension worldwide are fibromuscular dysplasia in the young and atherosclerosis in older adults. On the Indian subcontinent, however, Takayasu arteritis or nonspecific aortoarteritis is the main cause of renovascular hypertension in young adults, as well as in children, accounting for 59% to 80% of all cases in these groups. In older adults, as elsewhere, atherosclerosis is the most common cause.

Takayasu arteritis is a granulomatous large-vessel vasculitis (mainly affecting the aorta and its major branches) of unknown cause predominantly affecting young females in their second and third decades. It was first reported from Japan and has high prevalence among Asians. The pathology is characterized by the involvement of all arterial layers of the vessel (i.e., panarteritis) with a variable inflammatory infiltrate including acute exudative, chronic, and granulomatous inflammation, situated mainly in the media and adventitia, whereas hyperplasia and neovascularization are observed in the intimal layer. Inflammatory lesions later progress to fibrosis in the arterial wall, resulting in narrowing of the lumen.

Aortoarteritis has been classified into the following types, according to the site of involvement.

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  Type I affects the branches of the aortic arch.

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  Type IIa affects the ascending aorta, aortic arch, and its branches.

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  Type IIb affects the ascending aorta, aortic arch, and its branches and the descending thoracic aorta.

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  Type III affects the thoracic aorta, abdominal aorta, and/or renal arteries.

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  Type IV affects the abdominal aorta and/or renal arteries.

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  Type V is a combination of types IIb and IV.

Involvement of a coronary or pulmonary artery is indicated by appending the suffix C (+) or P (+) to any of the types. Type IV is common in India, whereas I and IIa are common in Japan.

The renal artery is narrowed at its ostium and in the proximal third with coexistent stenosis of the perirenal aorta. Bilateral renal artery stenosis is seen in about 50% of all patients ( Fig. 77.2 ). Nonspecific ischemic glomerular lesions resulting from arterial narrowing and hypertension are frequently observed in patients with renal artery involvement. The disease activity is measured by inflammatory markers such as erythrocyte sedimentation rate and C-reactive protein. Vascular imaging like ¹⁸ F-fluorodeoxyglucose positron emission tomography/ computed tomography has good sensitivity to detect active vasculitis at diagnosis and during immunosuppression in Indian patients.

Takayasu arteritis.

Shown is bilateral renal artery narrowing (vertical arrows) with poststenotic dilation on the left side, dilation and irregularity of the abdominal aorta (black arrow) , and a large collateral vessel (horizontal arrow) arising from the inferior mesenteric artery.

Oral steroids (prednisolone 0.5–1 mg/kg), along with either mycophenolate mofetil, azathioprine, leflunomide, cyclophosphamide, or methotrexate, are the initial treatment of choice in active disease. ^, Biologics such as anti–tumor necrosis factor–α agents and tocilizumab may be useful in patients refractory to conventional drugs. Symptomatic vascular lesions in the renal artery may require endovascular stenting and, in rare cases, renal autotransplantation.

In those who progress to ESKF, creating a vascular access for HD is difficult in the presence of extensive vascular involvement, congestive heart failure, and pulmonary arterial hypertension. The usual cause of death is congestive heart failure.

Obstructive nephropathy due to urolithiasis is common in Pakistan and contiguous parts of northern India. This constitutes what has been referred to as a “renal stone belt,” where nephrolithiasis is responsible for 5% of all cases of ESKD.

The available literature on urinary calculi shows a different stone pattern across the world, highlighting different geographic and causative factors. Studies in northern India have shown that most calculi (>90%) are calcium oxalate stones, predominantly calcium oxalate monohydrate (80%). Apatite, struvite, and uric acid stones account for <2% each. This incidence of calcium oxalate monohydrate stones is significantly higher than that in Western countries, where such stones constitute up to 50% of the total. Typically, staghorn calculi are composed of calcium magnesium ammonium phosphate. However, in Indian studies, even staghorn calculi are found to be made up predominantly of calcium oxalate. The high incidence of nephrolithiasis in India is related to inherited metabolic disorders, dietary factors, and working in high ambient temperatures combined with poor daily water intake. ^, Faith in the efficacy of indigenous medicines to dissolve stones may cause delays in surgical intervention and hastens the development of renal failure. Nephrolithiasis is discussed in more detail in Chapter 40 .

Unlike in Western nations, the concept of health insurance (both government funded and private) is still in a primitive stage on the Indian subcontinent. The costs of RRT, therefore, often must be borne by most patients out of their own funds. Some government and private organizations cover the cost of treatment of employees and their dependents as part of employment benefits. The overall cost of RRT in patients with ESKF is less in dollar terms than in the industrialized countries because of the lower staff salaries and low cost of drugs. Nevertheless, it is still several times higher than the current per-capita health care expenditure and remains out of reach for most of the population. In a survey from South India, 91% of patients with HD experienced catastrophic health care expenditure and 77% engaged in distress financing. Provision of medical subsidy is not associated with easing of financial hardship. In a state-funded HD program, 63.5% stopped taking treatment for ESKF (stopped coming to HD centers). Costs other than that of HD, like medicines and travel expenses, were not covered. This probably led to higher dropouts and mortality. Similar high dropout rates (18%) were observed at the Sindh Institute of Urology and Transplantation, which provides free dialysis in Pakistan, illustrating that the provision of free dialysis is not enough to overcome access barriers in the region. The cost of dialysis is also influenced by late presentation, with resulting poor clinical status that necessitates hospitalization. Poor hygiene, hot and humid climate, and overcrowding predispose to a variety of life-threatening infections. In one study, 10.5% of all patients initiated had tuberculosis. The union government of India has launched the Pradhan Mantri National Dialysis Programme, which operates through designated district-level centers to provide dialysis to patients. Apart from this, eligible patients can receive dialysis in other hospitals that are reimbursed under the National Health Protection Scheme (launched in 2018), later renamed Ayushman Bharat Pradhan Mantri Jan Arogya Yojana. HD services have grown using the public-private partnership model under Pradhan Mantri National Dialysis Programme. In this model, governments contract private entities to finance, build, and operate dialysis units at an agreed-upon rate. A public-private partnership offers several advantages, such as economies of scale through strategic purchasing and process efficiencies, scalable training of workforce, opportunities to implement standard operating procedures, and monitoring of quality.

More than 4950 HD centers existed in India as of 2022, with the majority in the private sector. There were 174,478 patients on maintenance HD as of 2018. Affordable HD through government support is available in 1405 centers in India. Pakistan had 140 dialysis centers in 2004, which increased to 894 in 2023. In both countries, many dialysis units are small, minimal-care facilities, owned and looked after by non-nephrologists or even technicians.

More than 50% of CKD patients visited a nephrologist for the first time with CKD stage V. This makes the creation of vascular access for HD difficult, and patients are usually started on temporary dialysis catheters. Decisions on the frequency and duration of HD sessions are based on patient symptomatology, financial considerations, and availability of dialysis slots. Most patients undergo two 4-hour sessions every week. Dialyzer reuse is practically universal, and reprocessing is often performed manually. The absence of regulation by the government or professional societies has prevented standardization of dialysis procedures including the establishment of minimum standards for dialysis machines, water quality, type of dialyzers, and reuse policies.

Viral hepatitis is among the most common viral infections encountered in patients undergoing dialysis. The prevalence of hepatitis B and C in dialysis units varies between 2% and 42% and 4% and 45%, respectively. Hepatitis B vaccination, despite low seroconversion rates, has reduced the prevalence among patients in India. Some HD centers still have a high prevalence of hepatitis B infection. After initiation of HD, 0.7% of seronegative patients turn seropositive. Many ESKD patients undergo transplantation with incomplete hepatitis B vaccination schedules and complete the schedules after getting a kidney transplant. Hepatitis C virus (HCV) has emerged as the predominant cause of viral hepatitis in patients undergoing maintenance HD. The annual incidence of HCV infection as detected by anti-HCV antibodies in HD patients was reported to be as high as 18%, compared with about 2% in patients receiving continuous ambulatory PD. The prevalence of HCV by testing HCV RNA in a study was 8%. In another study, 16.3% seroconverted to HCV RNA positive, within 6 months of initiation of HD. The high incidence of HCV in HD units could be related to the high prevalence of HCV seropositivity in patients undergoing HD, total transfused blood volume, lack of enforcement of universal precautions, and high comorbid illness burden. It has been shown that the isolation of HCV-infected patients during HD significantly decreases the HCV seroconversion rate, from 36.2% to 2.7%.

Malnutrition affects most patients receiving dialysis in this region. This leads to a high incidence of tuberculosis. Protein-energy wasting is present in 68% to 93% of patients on dialysis from middle and lower socioeconomic strata, and 41% were underweight. The protein and calorie-deficient diet, delay in initiation of dialysis, inadequate dialysis, and infections contribute to this problem. In most of the dialysis units in India, nutritional information is given by health professionals rather than a renal dietician, which is often inadequate. There is also a high prevalence of fatigue, depression, and sleep disturbances.