Sudden onset of dyspnea in a woman with skin lesions and lung cysts.

A 40-year-old female presented with complaints of sudden onset left sided chest pain, dry cough, and shortness of breath of one day duration.

On admission she was anxious, cyanosed, dyspnoeic and had obvious respiratory distress. She had an oxygen saturation of 78% while breathing room air, respiratory rate of 30/minutes, blood pressure of 140/90 mmHg, and a pulse of 126/minute. Respiratory examination revealed decreased movements, hyperresonance on percussion and distant lung sounds involving the entire left hemithorax. There were multiple, thick, fibrous, reddish-brown papules around the nose, cheeks, and chin conglomerulating to form a characteristic butterfly-shaped pattern [Figure 1a]. Besides this, there were fibromatous plaques over forehead and scalp [Figure 1a]. Her back revealed multiple ash leaf shaped hypopigmented macules and toenails revealed periungual fibromas [Figure 1b]. Her past history revealed that she had mild learning difficulty and had studied till fifth standard and was un-married.

Figure 1a

Multiple angiofibromas over nose, cheeks, and chin also seen fibromatous plaque over forehead

Figure 1b

Periungual fibromas: Skin colored growth arising beneath the proximal nail fold of toe nails

Laboratory investigations including hemogram and routine biochemistry were normal. Chest radiograph showed hypertranslucent left hemithorax [Figure 2a]. Computed tomography of chest revealed left sided pneumothorax and moderate sized right pleural effusion [Figure 2b]. The lung parenchyma revealed bilateral, multiple, variable sized cysts [Figure 2b] with normal intervening lung and preserved volumes. Diagnostic pleurocentesis revealed milky fluid, which was exudative lymphocytic predominant with pleural fluid proteins of 4g/dl, sugar of 100mg/dl, LDH of 344 U/L, pH of 7.60, triglycerides of 130 mg/dl, and cholesterol of 30 mg/dl. Abdominal ultrasound revealed bilateral multiple angiomyolipomas in the kidney and liver.

Figure 2a

Chest radiograph showing left hemithorax pneumothorax

Figure 2b

Computed tomogram chest showing bilateral well defined thin walled cysts and left pneumothorax and right sided effusion

QUESTION

Q 1: What is your diagnosis?

ANSWER

Pneumothorax secondary to tuberous sclerosis associated pulmonary lymphangioleiomyomatosis (LAM).

LAM is a rare interstitial lung disease, which occurs sporadically or in association with tuberous sclerosis complex (TSC)[12] and exclusively affects women, in their reproductive years. LAM is characterized pathologically by abnormal proliferation of smooth muscle cells in the lungs and in thoracic and retroperitoneal lymphatics. Patients with LAM usually present with chronic dyspnea and cough and less commonly with spontaneous pneumothorax.[1] Our case had pneumothorax as the initial presentation of LAM.

The High Resolution Computed Tomography (HRCT) finding of bilateral thin-walled pulmonary cysts with normal intervening parenchyma between the cysts, in women of childbearing age is virtually diagnostic of LAM.

LAM should be differentiated from other cystic lung diseases like langerhans cell histiocytosis and centrilobular emphysema. In centrilobular emphysema, the borders of the cystic spaces are not discrete and “centrilobular dot” is frequently seen. In Langerhans cell histiocytosis, the cyst walls are thicker and more bizarre in shape and the intervening parenchyma between the cysts contains nodules.

The diagnosis of pulmonary LAM requires an HRCT scan and either a lung biopsy fitting the pathological criteria for LAM or a compatible clinical context such as clinically confirmed tuberous sclerosis, angiomyolipoma (kidney), or thoracic or abdominal chylous effusion or lymphangioleiomyomas or lymph-node involved by LAM and definite or probable TSC.[3] Our case had characteristic HRCT findings, tuberous sclerosis, chylous pleural effusion, and angiomyolipoma in kidney and liver thus allowing us to make definite clinical diagnosis of LAM in association with tuberous sclerosis.

LAM is extremely difficult to treat and has a poor prognosis. As LAM is rare, there are no controlled trials of its management. Current treatment strategies based on estrogen antagonism are empiric and of unproven efficacy.[34] Supportive treatment includes management of airflow obstruction with bronchodilators and oxygen for hypoxemia. Pleurodesis is recommended even for first episode of pneumothorax since the recurrence rate is high.[34] An intercostals chest tube drainage and iodopovidone pleurodesis was done for the left sided pneumothorax and therapeutic tap was done for right sided moderate chylous effusion besides dietary modification for chylous effusions. Repeat chest roentogram done at one year did not reveal any recurrence of pneumothorax.