Paediatrics: how to manage acute respiratory distress syndrome

Trimethoprim-sulfamethoxazole-induced lung injury: a case report

Background

Trimethoprim-sulfamethoxazole (TMP-SMX) is a commonly used antibiotic. While cutaneous adverse drug reactions associated with TMP-SMX are commonly recognized, lung toxicity induced by TMP-SMX is an unusual condition, with scattered reports of hypersensitivity pneumonitis, acute fibrinous organizing pneumonia, interstitial lung disease and acute respiratory distress syndrome. Reports of TMP-SMX-associated drug-induced lung injury (DLI) are rare in the pediatric population and its pathogenesis is not well understood. Diagnosis of DLI remains a challenge, given the wide range of clinical presentations that overlap with other conditions and the lack of diagnostic tests. In this report, we describe a case of TMP-SMX-induced lung injury in an eight-year-old child.

Case Description

An eight-year-old girl presented in respiratory failure with acute symptoms of shortness of breath, fever, maculopapular rash and vomiting. This was associated with pneumonitis, pneumothorax, pneumomediastinum and subcutaneous emphysema on imaging. She had been on 25 days of TMP-SMX for treatment of Group D Salmonella bacteremia and osteomyelitis that was diagnosed prior to this current presentation. TMP-SMX was discontinued on admission due to concerns of possible drug reaction. Extensive infective, autoimmune and immunologic workup did not reveal the cause of the respiratory failure. Considering the absence of an alternative explanation for her clinical presentation and similarities in clinical courses to other reported cases, she was eventually diagnosed with TMP-SMX-associated DLI. She received a course of corticosteroids with subsequent clinical improvement and was weaned off home oxygen therapy a few months after her discharge from the hospital.

Conclusions

Diagnosis of DLI can be challenging. The early identification of DLI and discontinuation of culprit drug is essential in its management. Further understanding of the underlying pathophysiology and risk factors for TMP-SMX-associated DLI is required.

Management and outcomes of acute post-streptococcal glomerulonephritis in children

Acute post-streptococcal glomerulonephritis (APSGN) is the major cause of acute glomerulonephritis among children, especially in low- and middle-income countries. APSGN commonly occurs following pharyngitis due to the activation of antibodies and complements proteins against streptococcal antigens through the immune-complex-mediated mechanism. APSGN can be presented as acute nephritic syndrome, nephrotic syndrome, and rapidly progressive glomerulonephritis, or it may be subclinical. The management of APSGN is mainly supportive in nature with fluid restriction, anti-hypertensives, diuretics, and renal replacement therapy with dialysis, when necessary, as the disease is self-limiting. Congestive heart failure, pulmonary edema, and severe hypertension-induced encephalopathy might occur during the acute phase of APSGN due to hypervolemia. APSGN generally has a favorable prognosis with only a small percentage of patients with persistent urinary abnormalities, persistent hypertension, and chronic kidney disease after the acute episode of APSGN. Decreased complement levels, increased C-reactive protein, and hypoalbuminemia are associated with disease severity. Crescent formations on renal biopsy and renal insufficiency on presentation may be the predictors of disease severity and poor outcomes in APSGN in children.