Keywords
Pleurodesis - pneumothorax - histiocytosis
Introduction
Langerhans cell histiocytosis (LCH) is a rare disease characterized by the accumulation
of pathological histiocytes. It presents in children in several forms with the multisystem
involvement of skeletal, skin, liver, spleen, and lung manifestations being the classical
presentation. Isolated pulmonary LCH without other system involvement is uncommon
in children.[1] Pulmonary LCH is characterized by initially nodules and progressively cystic lung
disease with a tendency for spontaneous pneumothorax. We present here a child who
presented with respiratory failure with a provisional diagnosis of miliary tuberculosis
who was ultimately diagnosed with pulmonary LCH. The case is presented to highlight
the challenges faced in the diagnosis and also to present the role of pleurodesis
in the treatment of children with recurrent pneumothorax due to pulmonary LCH.
Case Report
A 5-year-old girl from rural South India presented to the Pediatric Intensive Care
Unit (PICU) of our institution in respiratory failure. She had been treated at two
other pediatric units for progressive respiratory distress and fever for the past
1 month. The symptoms of fever and respiratory distress had been insidious in onset
and had progressed over 2-month interval. Short courses of antibiotics had not improved
her symptoms. Based on her worsening respiratory distress and chest X-ray findings
which were interpreted as miliary tuberculosis, she had been started on antitubercular
treatment before referral. As her symptoms did not improve on antitubercular treatment
and her respiratory distress worsened, she was referred to our PICU for ventilator
support.
In the PICU, she was intubated and started on mechanical ventilation and supportive
care. She developed bilateral pneumothoraces requiring intercostal drainage tubes.
Following extubation considering the nonresolution of symptoms and unusual occurrence
of pneumothorax in a child with miliary tuberculosis, a chest computed tomography
(CT) was performed [Figure 1]. This revealed multiple nodules and thin-walled cysts all over both lungs. Many
cysts were subpleural. This characteristic radiological picture suggested LCH. Closed
lung biopsy was attempted, but the biopsy findings were noncontributory. The child
continued to have respiratory distress and oxygen requirement with bilateral extensive
coarse crepitations. She had multiple episodes of worsening of respiratory distress
with increased oxygen requirement due to repeated episodes of fresh pneumothoraces
on both sides. Besides her respiratory symptoms and signs, she had no other findings
to suggest LCH of other organs. Evaluation of blood counts, skeletal survey, and liver
function tests was all normal. Considering the typical radiological findings of LCH,
the plan was to give her a trial of chemotherapy as per the LCH III protocol (Vinblastine
and prednisolone). She was also started on intensive nutritional supplementation.
After 2 weeks of therapy, her general condition had not significantly improved and
she continued to have episodes of pneumothorax requiring new intercostal draining
tubes. In consultation with pulmonary medicine, therapeutic pleurodesis was planned
with povidone-iodine. She was given two doses of povidone-iodine on both sides and
tolerated the treatment well. After 4 weeks of chemotherapy, her oxygen requirement
had reduced and intercostal drain tubes were removed. She tolerated this well with
no recurrence of pneumothorax. Her interval assessment at 6 weeks showed a significant
improvement in the lung parenchyma but the persistence of few nodules and cysts [Figure 2]. A second 6-week induction course of chemotherapy was administered followed by maintenance
chemotherapy for 6 months. She is currently well with no respiratory signs and symptoms
with lung imaging showing no nodules or cysts. She has gained weight and has no active
disease on follow-up.
Figure 1: Serial chest X-rays and chest computed tomography showing bilateral pneumothorax
with multiple nodules and cysts on both lungs at diagnosis
Figure 2: X ray and CT chest post chemotherapy and bilateral povidone iodine pleurodesis
showing residual cysts but complete resolution of pneumothorax. (Six weeks from diagnosis)
Discussion
Up to 50% of children with multisystem LCH will have lung involvement. However, isolated
lung involvement in children is very uncommon.[1] Few case reports describe this entity.[2]
[3]
[4]
[5]
[6] Pulmonary LCH is often complicated by pneumothorax which can occur due to previously
formed cysts when active LCH causes parenchymal tissue damage. The chemotherapy for
systemic LCH does not prevent the occurrence of pneumothorax. The case presented here
has the following interesting features.
This case had radiology suggestive of miliary mottling at presentation. Tuberculosis,
a common concern in the developing world is a plausible clinical possibility for a
child with chronic respiratory symptoms and signs who presents with a miliary pattern
on chest X-ray. However, the differential diagnosis of miliary mottling is wide.[7] Other infective etiology besides tuberculosis such as histoplasmosis, blastomycosis,
and mycoplasma could be considered. Sarcoidosis, pneumoconiosis, and pulmonary alveolar
microlithiasis are some of the noninfective causes to be considered. The radiological
findings of pulmonary LCH are varied.[8] The typical reticulonodular pattern with cysts may easily be missed on plain X-rays
and better visualized on chest CT scans. The initial presentation with small nodules
may mimic the radiology seen in miliary tuberculosis causing a delay in the diagnosis.[9] The characteristic finding of bilateral pneumothorax may point more toward LCH,
but there are a few reports of miliary tuberculosis also presenting with pneumothorax,
further complicating the clinical and radiological approach to diagnosis.[10]
[11]
[12] Coexistent pulmonary LCH and tuberculosis can occur and has been reported in adults
but not in children.[13] Every effort should be made to prove the diagnosis of LCH by histopathological diagnosis,
especially before starting chemotherapy. Although a biopsy was attempted in our case,
it was noncontributory. Given the poor general condition of this child and the degree
of respiratory compromise, it was decided to not attempt a second lung biopsy.
Besides the diagnostic challenges, this case also required the uncommon therapeutic
intervention of pleurodesis. The need for pleurodesis is rare in children and limited
to cases of spontaneous primary pneumothorax and chylothorax. While historically the
chemicals used for pleurodesis were talc and tetracycline, more recently povidone-iodine
has found favor with respiratory physicians for pleurodesis.[14]
[15] It is well tolerated with no major complications. There are very few reports of
chemical pleurodesis being performed for pulmonary LCH in children.[16]
[17] Rarely, surgical pleurodesis has been performed.[18] Previous care reports from the literature have described how the treatment of pulmonary
LCH with only chemotherapy and chest tubes is associated with a prolonged therapy
often complicated by infections (including empyema).[19] Such long periods of treatment may be life-threatening in the developing countries.
However given the rarity of this scenario, there are no standard guidelines regarding
the optimal timing and choice of pleurodesis in children with pulmonary LCH. The rapid
resolution of symptoms of recurrent pneumothorax after pleurodesis in our patient
allowed for early removal of chest tubes and faster recovery.
The current chemotherapy protocols for LCH help in preventing further disease progression
in the lungs. However, they do not help prevent frequent pneumothorax. Although lung
is no longer considered a risk organ in Histiocyte Society protocols for treatment,
the need for multiple chest tube insertions, and can contribute not only to morbidity
but also to mortality in pulmonary LCH. Chemical pleurodesis with povidone-iodine
is a simple and effective procedure, especially in children who have recurrent episodes
of pneumothorax in LCH.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms.
In the form the patient(s) has/have given his/her/their consent for his/her/their
images and other clinical information to be reported in the journal. The patients
understand that their names and initials will not be published and due efforts will
be made to conceal their identity, but anonymity cannot be guaranteed.
