A 58-year-old man, with a history of gout and hypertension, has been a surgical user since 2011 due to nodal rhythm and has been a single kidney donor for more than thirty years to a sister with renal disease of unknown etiology.
She consulted in 2011 for a 3-month history of general malaise associated with episodes of low blood loss, which is added 2 weeks prior to her evaluation, monoarthritis of the left ankle with colpurine.
Purpuric lesions appear in the lower limbs.
Highlights in proteinuria increment 3.300 x mm3, VHS 90 mm/h, rise of basal creatinine from 1.5 to 3.69 mg/dL with non-dysmorphic hematuria 50 x field and (+).
PPD was taken that was 18 mm, viral serology (HIV, hepatitis B and C), negative.
Antinuclear antibodies (ANA) (-), antineutrophil cytoplasmic antibody (ANCA) (+), mild pattern indeterminate, with ELISA for PR3 (-), antinormal (1.0 mg/dL) and tricyclic (180 mg)
Chest and abdominal CT: pulmonary nodule with appearance on right base, in addition to a ground glass area and bronchiectasis in both fields.
Abdominal examination revealed nephromegaly.
Fibrobronchoscopy with bonquioalveolar lavage ruled out infection with bronchiectasis (-).
It is interpreted as vasculitis and methylprednisolone 500 mg/day is indicated for 3 days, recovering creatinine up to 1.49 mg/dL.
She was discharged with prednisone and colchicine.
The patient continued treatment and consultation the following year for the same symptoms of hemoptysis and renal failure associated with hematuria and proteinuria.
Nine studies showed hypocomplementemia and equal magnitude, with negative rheumatologic serology, except for rheumatic factor, positive in 160 U/mL.
Cryoglobulins were negative and immunoglobulin count showed an IgG of 2,898 mg/dL (normal < 1,600).
Again, the bacteriological study, including Mycobacterium research, showed no findings.
She was discharged with favorable steroidal treatment.
Return to consultation on two more occasions due to the same situation, 2014 and 2015 when a renal biopsy is performed, with the consent of the patient, considering the risk in his condition as a single kidney.
Biopsy revealed lymphoplasmacytic interstitial nephritis with extensive storiform pattern fibrosis (arreolinated).
Immunohistochemistry confirmed positivity for IgG4 in leukocytes of the infiltrate, with an IgG4/IgG ratio of 63%.
Acquired electronics showed deposits and malformations in the tubular basement membrane and interstice.
We conclude IgG4-related interstitial nephritis, more pulmonary involvement probably associated with the same disease.
Treatment was initiated with prednisone 60 mg/day associated with isoniazid for the treatment of latent tuberculosis.
After 6 months of treatment, she had 5 mg of prednisone, creatinine of 1.45 mg/dL, eosinophils of 245 x mm3 and complement C3/C4 of 104/24 mg/dL.
