Tubulointerstitial Nephritis

Excerpt

Tubulointerstitial nephritis (TIN), also called interstitial nephritis, was first described in 1898 by a pathologist who noted that post-mortem biopsies of patients with streptococcal infection commonly showed nonsuppurative inflammatory lesions in the kidney interstitium. In this group of disorders, nephritis consists of inflammatory cells and fluid within the extracellular matrix of the renal interstitium, along with infiltration of renal tubular cells by macrophages, lymphocytes, plasma cells, and sometimes eosinophils. The glomeruli are usually spared unless chronic TIN develops. TIN can be classified as acute or chronic based on the underlying etiology, duration, and histology. By far, the most common cause of TIN is drug-induced, also called allergic, acute interstitial nephritis, which makes up 70% to 75% of TIN cases and is described in a separate StatPearls review. This review describes the etiologies and treatments of non-drug-related TIN, which comprise 20% to 25% of cases.

There are multiple causative factors of non-drug-related TIN, such as idiopathic, genetic, immune-mediated, and infectious (viral, bacterial, parasitic, or fungal). Associated systemic conditions include inflammatory bowel disease, sarcoidosis; systemic lupus erythematosus (SLE); Sjögren disease; immunoglobulin G4-associated autoimmune disease; anti-tubular basement membrane disease; and tubulointerstitial nephritis and uveitis syndrome (TINU).

A delay in diagnosis due to TIN's nonspecific signs and symptoms is frequently seen, and such delays can have serious consequences. Many attempts have been made to establish an efficient, reliable diagnostic protocol to quickly exclude other differentials through diagnostic tests, clinical history, and disease presentations. However, diagnosing TIN often remains challenging. This review summarizes the diagnosis and management of the various forms of tubulointerstitial nephritis.

Autosomal dominant tubulointerstitial kidney disease is described in StatPearls companion reference on "Autosomal Dominant Tubulointerstitial Kidney Disease."