Antithyroid drugs

A Spotlight on Drug-Induced Vasculitis

PURPOSE OF REVIEW

Drug-induced vasculitis (DIV) is a rare form of vasculitis related to the use of various drugs. DIV primarily affects small to medium size vessels, but it can potentially involve vessels of any size. Differentiating between primary systemic vasculitis and DIV can be challenging; however, it is crucial, so that the offending agent can be discontinued promptly.

RECENT FINDINGS

The clinical phenotype of DIV is protean and depends on the size of the affected vessels. It ranges from arthralgias, to an isolated cutaneous rash, to severe single or multi-organ involvement. While withdrawal of the offending drug is the most important step in management, a significant number of patients require immunosuppressive therapy for varying periods of time. DIV can affect any vascular bed size, leading to protean vasculitic syndromes. Increased awareness among general practitioners, specialty, and subspecialty physicians is crucial for early recognition, and withdrawal of drug for better outcomes.

Propylthiouracil-induced organizing pneumonia: A case report

RATIONALE

Propylthiouracil (PTU) is a common antithyroid drug which can treat hyperthyroidism effectively. PTU is, however, associated to multiple adverse effects. In rare case, PTU can cause interstitial pneumonia.

PATIENT CONCERNS

A 40-year-old woman presented with dyspnea and was diagnosed with pulmonary infection at the first time. After the treatment with moxifloxacin, her symptoms still got worse.

DIAGNOSIS

The lung tissues biopsy confirmed the diagnosis of organizing pneumonia (OP) and the administration of PTU suggested the diagnosis of PTU-induced OP.

INTERVENTION

Withdrawal of PTU and the administration of methylprednisolone.

OUTCOMES

The patient's symptoms relieved significantly 1 month later and lung computed tomography (CT) scan also demonstrated significant reduction of lung lesions.

LESSONS

Here we report the first case of histologically confirmed OP induced by PTU and conduct a literature review of the cases of PTU-induced interstitial pneumonia. The awareness of PTU-induced OP can help physicians reduce the possibility of misdiagnosis.

Propylthiouracil-induced antineutrophil cytoplasmic antibody (ANCA)-associated renal vasculitis versus primary ANCA-associated renal vasculitis: a comparative study

OBJECTIVE

Renal involvement is frequently present in primary antineutrophil cytoplasmic antibody-associated small-vessel vasculitis (AAV) as well as propylthiouracil (PTU)-induced AAV. We analyzed the characteristics of patients with PTU-induced AAV with renal involvement and investigated the differences of the 2 diseases.

METHODS

Thirty-six patients with PTU-induced AAV, diagnosed from 1997 to 2010, were enrolled for study. Their data were compared with those of 174 patients with primary AAV diagnosed at the same time. Renal involvement was present in all patients.

RESULTS

There was a prominent proportion of young women with PTU-induced AAV (p < 0.01). They had lower levels of proteinuria and serum creatinine and higher estimated glomerular filtration rate (p < 0.01, p < 0.01, and p < 0.01, respectively). Clinical immunological abnormalities were less severe in patients with PTU-induced AAV. Patients with PTU-induced AAV had less organ involvement and lower Birmingham Vasculitis Assessment Score than patients with primary AAV (p < 0.01). Renal biopsies showed a lower proportion of glomeruli with crescents (p < 0.01). Interstitial inflammation was less severe in patients with PTU-induced AAV (p < 0.05). Similarly, interstitial fibrosis and tubular atrophy were less severe in patients with PTU-induced AAV (p < 0.01, p < 0.05, respectively). Renal survival and total survival were better in patients with PTU-associated vasculitis (p < 0.05, p = 0.01).

CONCLUSION

Clinical and histopathological abnormalities were less severe in patients with PTU-induced AAV and most of them had a good prognosis.