potentially life - threatening systemic diseases like hematologic disorders can initially present with isolated ocular symptoms . therefore , accurate ophthalmologic assessment and prompt ancillary testing facilitates timely diagnosis and subsequent therapy in undefined cases . thus , we report of a patient presenting with isolated decreased monocular vision . ophthalmic and clinical workup led to the diagnosis of acute lymphoblastic leukemia ( all ) . only a sparse number of similar cases have been reported in the literature [ 1 , 2 , 3 , 4 , 5 ] . we would like to elucidate the striking correlation between the amount of subretinal fluid , total leukocyte count and visual acuity . the 28-year - old female patient presented with decreased central vision in her right eye since getting up that morning . the initial corrected visual acuities were 20/40 ( od ) and 20/20 ( os ) , but it dropped to 20/200 ( od ) on day 5 of clinical follow - up . fundus examination showed a vital optic nerve head , but the macula of the right eye presented with a prominent center - involving serous neurosensory retinal detachment and whitish - yellowish choroidal infiltrations . it was less prominent in the central macula of the left eye , but extensive serous detachment was present in the area of the papillomacular bundle ( fig . 1 ) at the inferotemporal vascular arcade . optical coherence tomography ( oct ) confirmed prominent subretinal fluid overlying an area of choroidal thickening . fluorescein angiography detected multifocal areas of leakage at the level of the retinal pigment epithelium ( fig . 1 ) . due to her initial findings , the primary care ophthalmologist considered central serous retinopathy or chorioretinitis of unknown origin as potential differential diagnoses . follow - up on day 3 revealed further deterioration of symptoms despite proper treatment with oral prednisone and ketorolac eyedrops . upon referral , the leukocyte count ( normal range in parentheses ) was found to be substantially increased to a total of 38.2 g / l ( 4.010.0 ) [ erythrocytes 4.65 g / l ( 3.84.2 ) , thrombocytes 30 g / l ( 150380 ) , blasts 87% ( 0.0 ) and increased ldh 645 u / l ( 100250 ) ] . considering this life - threatening situation , the patient was admitted to the department of hematology . upon further enquiry and more detailed medical history , on consecutive ophthalmic examinations , her vision dropped in both eyes as shown in figure 2 . the clinical findings and oct images demonstrated a striking relationship between visual acuity , amount of subretinal fluid and leukocyte count . to depict this significant correlation , the thickness of submacular fluid was measured and compared to vision and leukocyte count ( fig . leukemia is a potential life - threatening malignant disease characterized by uncontrolled proliferation and accumulation of mature and premature malignant leukocytes in the bone marrow with a subsequent peripheral distribution . different forms of leukemia can be classified by their cell of origin and by their time of duration . detailed subclasses are described by their genetic and immunochemical characteristics [ 7 , 8 ] . the overall incidence rate of all is 1.28/100,000 per year showing a bimodal distribution with higher rates in younger ( 014 years ) and older patients ( over 54 years ) . direct leukemic manifestations as infiltrates have been reported of the optic nerve , choroid , retina , iris , ciliary body and anterior chamber . indirect leukemic manifestations such as central serous chorioretinopathy overlaying choroidal infiltrations , retinal vascular sheathing and subconjunctival , anterior chamber , intraretinal , or intravitreal hemorrhages have been found . histopathology of postmortem specimens performed by kincaid and green   at the wilmer ophthalmological institute between 1923 und 1980 found ocular involvement in 82% of patients with all . reddy et al .   reported ocular findings in 35.4% of 288 newly diagnosed cases of leukemia in children and adults , but obvious clinical symptoms were only present in 10% . ocular involvement in hematologic disease entities may benefit from immediate systemic chemotherapy of all as they are usually not treated directly . the leukemic infiltrates were found in almost any location in the eye ; however , they are most frequent in the choroid with primary or compressive involvement of the adjacent choriocapillaris . the consecutive dysfunction of the retinal pigment epithelium and the outer blood - retina barrier may ultimately lead to serous retinal detachment as observed in our patient [ 12 , 13 ] . these findings correlate well with the multifocal areas of leakage at the level of the retinal pigment epithelium shown by fluorescein angiography in our case . they suggested that an increased osmotic gradient caused by subretinal accumulation of high - molecular - weight immunoglobulins induces exudation . due to immediate induction of chemotherapy by the department of oncology and hematology , the leukocyte count of the patient declined adequately . upon her last visit to the department of ophthalmology her visual acuity improved to 20/40 ( od ) and 20/20 ( os ) , and the reduction of subretinal fluid showed an evidently positive correlation with regressing leukocyte counts ( fig . , her ocular biomicroscopic examination , oct and fluorescein angiography had resolved back to normal ( fig . this case report was conducted in accordance with good clinical practices . the authors state to have full control of all primary data and have no ethical conflicts to disclose .
this case illustrates that hematologic disorders must be considered as a potentially life - threatening cause for vision loss . 
 proper laboratory workup and timely interdisciplinary approach are essential to ensure the best possible care for ophthalmic patients . 
 historically , before the use of bone marrow biopsy , the ophthalmologist was often asked to assist in the diagnosis of leukemia . since ophthalmological symptoms may be the initial presenting signs of leukemia as highlighted in this case , the ophthalmogist is still of crucial importance .